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حرية الوصول المقاله
1 - بررسی تاثیر کاربرد پسماندهای لیگنوسلولزی(سبوس و ساقه برنج) بر ویژگیهای فرآورده چندسازه "چوب-سیمان"
میثم مهدی نیا مینا جان احمدی آرش فرج پور اصغر تابعی سعید کامرانیاین تحقیق به منظور بررسی تاثیر کاربرد پسماندهای لیگنوسلولزی سبوس و ساقه برنج بر ویژگیهای فراورده چندسازه "چوب- سیمان" ( ‎CB) ‎انجام گرفته است. بدین منظور، تخته هایی از چوب صنوبر و اختلاط چوب صنوبر و کلش برنج با سیمان پرتلند تیپ 2 ساخته شد. همچنین از خاکستر سبو أکثراین تحقیق به منظور بررسی تاثیر کاربرد پسماندهای لیگنوسلولزی سبوس و ساقه برنج بر ویژگیهای فراورده چندسازه "چوب- سیمان" ( ‎CB) ‎انجام گرفته است. بدین منظور، تخته هایی از چوب صنوبر و اختلاط چوب صنوبر و کلش برنج با سیمان پرتلند تیپ 2 ساخته شد. همچنین از خاکستر سبوس برنج به عنوان ماده پوزولانی در سه سطح (2،0و4 درصد) استفاده شد. جهت ارزیابی خواص کاربردی نمونه ها، مقاومت خمشی ‎(MOR)‎، مدول الاستیسیته ( MOE )، مقاومت برشی و میزان جذب آب WA)‎ ) و واکشیدگی ضخامت ( TS ) پس از 2 و 24 ساعت غوطه وری در آب براساس استانداردهای DIN68763‎ و ISO16983‎ اندازه گیری شد. نتایج نشان داد که با تغییر ماده لیگنوسلولزی از کلش برنج به مخلوط کلش و صنوبر، ویژگیهای مکانیکی بهبود می یابد ولی ویژگیهای فیزیکی افزایش می‌یابد. همچنین نتایج نشان داد زمانی که از 4درصد خاکستر سبوس برنج استفاده شد، بیشترین مقاومت خمشی، مدول الاستیسیته، مقاومت برشی و کمترین واکشیدگی ضخامت و جذب آب بعد از 2 و 24 ساعت در آب به دست آمد. تفاصيل المقالة -
حرية الوصول المقاله
2 - ارزیابی کارایی فیلترهای زیستی مختلف در تصفیه زهاب کشاورزی
علی کیانپور بهمن یارقلی احمد شرافتی کرامت اخوان گیگلوزمینه و هدف: با توجه به مصارف بالای آب در کشاورزی، سالانه حجم قابل‌توجهی زهاب تولید می‌شود. در حال حاضر حجم قابل‌توجهی از زهاب (فقط بالغ بر سه میلیارد متر مکعب در خوزستان) بدون استفاده سودمند وارد محیط شده و آلودگی منابع آب و خاک را در پی دارد. با توجه به بحران آب در کش أکثرزمینه و هدف: با توجه به مصارف بالای آب در کشاورزی، سالانه حجم قابل‌توجهی زهاب تولید می‌شود. در حال حاضر حجم قابل‌توجهی از زهاب (فقط بالغ بر سه میلیارد متر مکعب در خوزستان) بدون استفاده سودمند وارد محیط شده و آلودگی منابع آب و خاک را در پی دارد. با توجه به بحران آب در کشور، حفاظت کیفی از منابع آب و استفاده از منابع آب نامتعارف، به‌ویژه مدیریت کیفی زهاب و استفاده از آنها در کشاورزی و محیط زیست به‌عنوان امری ضروری مطرح می‌باشد.مواد و روش: این تحقیق در استان خوزستان و در بهار و تابستان سال 1399 با استفاده از زهاب کشت و صنعت میرزا کوچک خان و امیرکبیر انجام شد. این تحقیق برای ارزیابی کارایی فیلترهای زیستی با جنس بسترهای مختلف برای تصفیه زهاب‌های کشاورزی خوزستان با هدف کاهش آلودگی منابع پذیرنده و همچنین استفاده مجدد در کشاورزی اجرا گردید. در این تحقیق تأثیر چهار جنس مختلف فیلتر زیستی شامل خاک‌اره، ساقه پنبه، کاه و کلش گندم و پوسته برنج به‌عنوان عامل اصلی و سه زمان مانده 2، 5 و 10 روز به‌عنوان عامل فرعی موردبررسی قرار گرفت. فاکتورهای کیفی مورد پایش شامل pH، کدورت، EC (به‌عنوان شاخص شوری)، ازت کل، فسفر کل و BOD بود.یافته‌ها: نتایج تجزیه واریانس نشان می‌دهد که بین تیمارهای مختلف از نظر پارامترهای موردمطالعه، به غیر از pH، برای باقی فاکتورها در سطح یک درصد اختلاف معنی‌داری وجود دارد. بر اساس نتایج حاصله، بیشترین میانگین پالایش فاکتورهای کیفی مورد تحقیق بر اساس جنس فیلتر برای کدورت معادل 87/37 درصد و مربوط به تیمار ساقه پنبه است. برای EC، ازت کل، فسفر کل و BOD به ترتیب معادل 23/9،60/49، 50/46 و 97/59 درصد و مربوط به تیمار خاک‌اره می‌باشد. بر اساس نتایج حاصل میانگین بیشترین درصد کاهش آلودگی برای فاکتورهای موردبررسی مربوط به زمان‌ماند 10 روزه بوده که برای کدورت، EC، ازت کل، فسفر کل و BOD به ترتیب معادل 79/56، 97/12، 51/66، 49/53 و 20/80 درصد می‌باشد.نتیجه‌گیری: توجه به نتایج حاکی از عملکرد نسبتاً بهتر تیمار خاک‌اره در مقایسه با سایر تیمارها می‌باشد. این موضوع با توجه به وجود و فراوانی این ماده در سطح کشور از نظر امکان استفاده از آن حائز اهمیت می‌باشد. توجه به اثر زمان‌ماند هیدرولیکی، نسبت مستقیم راندمان با زمان‌ماند را نشان می‌دهد. ولی افزایش راندمان از زمان‌ماند 2 روز تا 5 روز (سه روز) معنی‌دارتر از افزایش زمان‌ماند از 5 روز به 10 روز (5 روز افزایش) می‌باشد؛ که این موضوع با توجه به غلظت آلاینده‌های موجود در زهاب، می‌تواند به‌عنوان عامل مهمی در انتخاب زمان‌ماند محسوب شود. بر این اساس، برای فاکتورهای موردبررسی فیلتر خاک‌اره و زمان‌ماند 5 روزه به‌واسطه عملکرد مناسب و اقتصادی‌تر بودن از نظر حجم و ابعاد سیستم توصیه می‌گردد تفاصيل المقالة -
حرية الوصول المقاله
3 - ارزیابی فعالیت ضد باکتری نانوذره های منیزیم اکسید در زئولیت ZSM-12 تهیه شده از پوسته برنج
آزیتا آل بویه افشین پوراحمد حسن کفایتیزمینه و هدف: پوسته برنج یک فراورده فرعی کشاورزی است که حدودا %22 وزن برنج را تشکیل می دهد. بنابراین، پوسته برنج به عنوان پسماند کشاورزی به وفور در کشورهای تولیدکننده برنج موجود است. بخش عمده ای از پوسته تولید شده از فرآوری برنج به صورت زباله سوزانده می شود که باعث ایجاد أکثرزمینه و هدف: پوسته برنج یک فراورده فرعی کشاورزی است که حدودا %22 وزن برنج را تشکیل می دهد. بنابراین، پوسته برنج به عنوان پسماند کشاورزی به وفور در کشورهای تولیدکننده برنج موجود است. بخش عمده ای از پوسته تولید شده از فرآوری برنج به صورت زباله سوزانده می شود که باعث ایجاد مشکلات زیست محیطی و بهداشتی بخصوص در کشورهای فقیر و در حال توسعه می شود. بنابراین، یافتن مسیری برای استفاده کامل از پوسته برنج بسیار مهم است. روش بررسی: در این مطالعه، ساخت و شناسایی زئولیت ZSM-12 با استفاده از خاکستر پوسته برنج به عنوان یک منبع سیلیس ارزان، و سنتز، شناسایی نانوذره های منیزیم اکسید در بستر زئولیت به روش واکنش حالت جامد و تبادل یونی گزارش شده است. فعالیت ضد باکتری نانوذره ها به روش تعیین حداقل غلظت ممانعت کننده از رشد و انتشار از دیسک، در مقایسه با آنتی بیوتیک های استاندارد، علیه باکتری های گرم منفی اشرشیاکلی و گرم مثبت استافیلوکوکوس اورئوس مورد بررسی قرار گرفت. یافته ها: نمونه های سنتز شده با استفاده از پراش اشعه ایکس، میکروسکوپ الکترونی روبشی، طیف سنجی پراش انرژی پرتو ایکس و میکروسکوپ الکترونی عبوری مورد ارزیابی و شناسایی قرار گرفتند. نتایج پراش پرتو ایکس، پیک های پراش هر دو ترکیب در نانوچندسازه MgO/ZSM-12 را نشان داد. بحث و نتیجه گیری: تصویر میکروسکوپ الکترونی عبوری نانوچندسازه اندازه نانوذره های منیزیم اکسید را حدود 35 نانومتر نشان داد. نانوکامپوزیت فعالیت ضد باکتری با حداقل غلظت مهار کنندگی g/mLµ 96 را در مقابل باکتری های اشرشیاکلی و استافیلوکوکوس اورئوس نشان داد. تفاصيل المقالة -
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4 - تأثیر غلظت بر بازده و زمان تعادل جذب سرب از محیط آبی توسط جاذب پوسته شلتوک
حسن جمالی ارمندی زمان شامحمدی حیدریاین تحقیق با هدف مطالعه تغییرات زمان تعادل و بازده جذب در غلظت های مختلف سرب انجام گرفت. برای این کار از جاذب پوسته شلتوک برای جذب سرب استفاده شد. آزمایش های جذب سینتیک برای تعیین زمان تعادل در غلظت های مختلف سرب انجام یافت. نتایج نشان داد که در غلظت های مختلف با افزایش أکثراین تحقیق با هدف مطالعه تغییرات زمان تعادل و بازده جذب در غلظت های مختلف سرب انجام گرفت. برای این کار از جاذب پوسته شلتوک برای جذب سرب استفاده شد. آزمایش های جذب سینتیک برای تعیین زمان تعادل در غلظت های مختلف سرب انجام یافت. نتایج نشان داد که در غلظت های مختلف با افزایش زمان تماس، مقدار سرب جذب شده در واحد وزن جاذب افزایش می یابد و فرایند جذب در غلظت های 1، 10، 20، 50، 100، 200 و 500 میلی گرم بر لیتر به ترتیب در مدت زمان های 60، 90، 105، 120، 90، 75 و 60 دقیقه به تعادل می رسد. با کاهش غلظت محلول از 500 به 1 میلی گرم بر لیتر، بازده جذب افزایش یافت به طوری که حداکثر بازده جذب برابر 98% در غلظت 1 میلی گرم بر لیتر به دست آمد. داده های آزمایش با استفاده از دو مدل سینتیک Ho and et al (1996) و Lagergren (1898) برازش داده شدند، نتایج نشان داد که جذب یون های سرب روی پوسته شلتوک از مدل Ho and et al پیروی می کند. نتایج حاصل از آزمایش های جذب ایزوترم با مدل های Langmuir و Freundlich مطابقت داده شدند. نتایج نشان داد که مدل Freundlich داده ها را بهتر توصیف می نماید. تفاصيل المقالة -
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5 - Removal of Bisphenol-A from Aqueous Solution Using Rice Husk Nanosilica: Adsorption Kinetics, Equilibrium and Thermodynamic Studies
Benjamin Olawale Orimolade Folahan Amoo Adekola Aderonke Aminat Mohammed Azeez Olayiwola Idris Oluwaseyi Damilare Saliu Taofeek YusufThis study evaluates the adsorption of bisphenol-A (BPA) from aqueous solutions using nanosilicaobtained from rice husk. Nanosilica (79 nm) was extracted from acid and thermal treated rice huskwaste. The rice husk nanosilica (RHS) was fully characterized through X-Ray D أکثرThis study evaluates the adsorption of bisphenol-A (BPA) from aqueous solutions using nanosilicaobtained from rice husk. Nanosilica (79 nm) was extracted from acid and thermal treated rice huskwaste. The rice husk nanosilica (RHS) was fully characterized through X-Ray DiffractionSpectroscopy (XRD), Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy(XRF) and Fourier Transmittance Infrared Spectroscopy (FTIR). The spectroscopic analyses resultsrevealed that the rice husk ash contains large fraction of amorphous silica. Batch adsorptionexperiments were carried out on BPA as a function of initial concentration, contact time, pH,adsorbent dosage and temperature. The maximum amount of BPA adsorbed was 4.267 mg/g withan optimum contact time of 45 min for 50 mg/L BPA solution at pH 8. The adsorption data wereanalyzed with adsorption isotherms and fitted best into the Langmuir model with R2 value of 0.994.The adsorption process followed the pseudo second order kinetics and was exothermic while thenegative value of Gibbs free energy obtained revealed that the process is feasible at lowertemperature. تفاصيل المقالة -
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6 - Synthesis of Unsymmetrical Ethers Catalysed by Polyvinyl sulfuric acid & PVSA / Nano RH SiO2 as a Novel Solid Acid Nanocomposite
roya moeinzadeh Ali Kiasat Hadi AsarehThe methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing of polyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability of the solid acid was investigated for the facile conversion of benzylic أکثرThe methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing of polyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability of the solid acid was investigated for the facile conversion of benzylic alcohols to the unsymmetrical ethers with aliphatic alcohols in the presence of the solid acid. Results show that the solid acid is an appropriate catalytic agent for these condensation reactions. The silica was also extracted from low-cost rice husk and the amorphous silicagel nanoparticles was prepared with solgel method. The polyvinyl sulfuric acid was supported on nano rice husk silica. Then the catalytic effect of this system was investigated for synthesis of unsymmetrical ethers which consisted of a combination of high acidic power for this solid acid and high- surface area of nanoparticles. Results show that totally catalytic effect of polyvinyl sulfuric acid supported on nano silica is more suitable than polyvinyl sulfuric acid. The reason for this is in its ability to produce the end products in shorter reaction times while having high isolated yields. تفاصيل المقالة -
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7 - Synthesis of Pyranopyrazole Compounds Using Heterogeneous Base Catalyst Based on 1,3,5-Triazine-2,4,6-Triamine Modified Nano Rice Husk Silica
Jamal Davarpanah Reza KhoramIn the current study, amorphous silica nanoparticles were easily extracted from rice husk ash. The target composite was synthesized by the direct incorporation of chloropropyl groups through the condensation of nanosilica and 3-chloropropyl trimethoxysilane and then gra أکثرIn the current study, amorphous silica nanoparticles were easily extracted from rice husk ash. The target composite was synthesized by the direct incorporation of chloropropyl groups through the condensation of nanosilica and 3-chloropropyl trimethoxysilane and then grafting of 1,3,5-triazine-2,4,6-triamine (Melamine) onto the propyl groups by the simple nucleophilic substitution reaction (RHA@Melamine). The resulting solid catalyst was characterized by infrared spectroscopy, scanning electron microscope and thermogravimetric analysis. The catalytic activity of this solid acid nanocomposite was probed through one-pot synthesis of 1,4-dihydropyrano[2,3-c] pyrazole via four-component couplings of aldehydes, hydrazine hydrate, ethyl acetoacetate and malononitrile under solvent-free conditions. In this reaction, RHA@Melamine shows good catalytic nature, easy to handle procedure, recycle exploitation and excellent isolated yields of products. تفاصيل المقالة -
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8 - Synthesis of Unsymmetrical Ethers Catalysed by Polyvinyl Sulfuric Acid & PVSA / Nano RH SiO2 as a Novel Solid Acid Nanocomposite
Roya Moeinzadeh Hadi Asareh Ali Reza KiasatThe methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing ofpolyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability ofthe solid acid was investigated for the facile conversion of benzylic alcohols أکثرThe methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing ofpolyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability ofthe solid acid was investigated for the facile conversion of benzylic alcohols to the unsymmetricalethers with aliphatic alcohols in the presence of the solid acid. Results show that the solid acid isan appropriate catalytic agent for these condensation reactions. The silica was also extracted fromlow-cost rice husk and the amorphous silica gel nanoparticles were prepared with sol- gel method.The polyvinyl sulfuric acid was supported on nano rice husk silica. Then the catalytic effect of thissystem was investigated for synthesis of unsymmetrical ethers which consisted of a combination ofhigh acidic power for this solid acid and high- surface area of nanoparticles. Results show that totallycatalytic effect of polyvinyl sulfuric acid supported on nano silica is more suitable than polyvinylsulfuric acid. The reason for this is in its ability to produce the end products in shorter reaction timeswhile having high isolated yields. تفاصيل المقالة -
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9 - Modification of silica with 2,4-dinitrophenylhydrazanomethylphenol for monosaccharide productions
Kasim Mohammed Hello Hayder Mihsen Mosa2,4-dinitrophenylhydrazanomethylphenol (DNPHMP) was immobilized onto silicate rice husk ash to form a heterogeneous catalyst denoted as RHDNPH. The elemental and EDX analysis of RHDNPH showed the nitrogen is incorporated into silica. The RHDNPH had 154.6 m2g-1 as a spec أکثر2,4-dinitrophenylhydrazanomethylphenol (DNPHMP) was immobilized onto silicate rice husk ash to form a heterogeneous catalyst denoted as RHDNPH. The elemental and EDX analysis of RHDNPH showed the nitrogen is incorporated into silica. The RHDNPH had 154.6 m2g-1 as a specific surface area. The FT-IR clearly showed the appearance of –NH and C=N absorption band at the expected range. The TGA curve shows that the RHDNPH was stable at the temperature of less than 200 °C. Hydrolysis experiments of cellulose were conducted in liquid face reaction at 140 °C, and 150 mg of catalyst mass in 11 h. The maximum hydrolysis of cellulose was 84 % with 100 % selectivity of glucose over the catalyst. The catalyst was simple in its preparation, stable during the cellulose hydrolysis in addition to repeatedly without a significant loss of its catalytic activity. تفاصيل المقالة -
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10 - Rice husk ash (RHA): A Highly efficient solid acid catalyst for the oxidation of alcohols and trimethylsilyl, tetrahydropyranyl and methoxymethyl ethers with CrO3
Farhad Shirini Masoumeh Abedini Mahnaz Shamsi-Sani Mohadeseh SeddighiA mild, efficient and fast method for the oxidation of alcohols and trimethylsilyl, tetrahydropyranyl and methoxymethyl ethers to their corresponding carbonyl compounds using CrO3 in the presence of rice husk ash (RHA) is reported. All reactions were performed at room t أکثرA mild, efficient and fast method for the oxidation of alcohols and trimethylsilyl, tetrahydropyranyl and methoxymethyl ethers to their corresponding carbonyl compounds using CrO3 in the presence of rice husk ash (RHA) is reported. All reactions were performed at room temperature in high to excellent yields. A new, efficient and green catalyst, heterogeneous reaction conditions, easy work-up of the products and high reaction rates are the main advantages of this method. تفاصيل المقالة -
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11 - Introduction of sulfonated rice husk ash as a highly efficient reusable catalyst for the protection of the hydroxyl group
Farhad Shirini Masoumeh Abedini Mahnaz Shamsi-Sani Mohadeseh SeddighiA mild, efficient and fast method for the trimethylsilyl (TMS), tetrahydropyranyl (THP) and methoxymethyl (MOM) protection of alcohols and phenols in the presence of sulfonated rice husk ash (RHA-SO3H) is reported. All reactions were performed at room temperature in hig أکثرA mild, efficient and fast method for the trimethylsilyl (TMS), tetrahydropyranyl (THP) and methoxymethyl (MOM) protection of alcohols and phenols in the presence of sulfonated rice husk ash (RHA-SO3H) is reported. All reactions were performed at room temperature in high to excellent yields. All the products are separated and compared with authentic samples and/ or identified using different types of methods including FT-IR, 1H NMR and 13C NMR spectroscopy. Ease of the preparation and handling of the catalyst, heterogeneous reaction conditions, reusability of the catalyst, easy work-up procedure and short reaction times are the main advantages of this method, which make this procedure useful and attractive addition to the available methods. تفاصيل المقالة -
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12 - Investigation efficiency of nano photocatalytic compound of TiO2 and rice husk silica in removal of reactive red 198 dye from synthetic aqueous solutions
Abdollrahman Mahmoodi Seyed Mahmood Mehdinia Ayat Rahmani Hamidreza NassehiniaThis study was performed with the aim of investigating the efficiency of the Nano photocatalytic of ultraviolet and titanium dioxide compound and rice husk silica adsorbent (UV/TiO2/RHS) in removal reactive red 198 dye from synthetic aqueous solutions. The removal of re أکثرThis study was performed with the aim of investigating the efficiency of the Nano photocatalytic of ultraviolet and titanium dioxide compound and rice husk silica adsorbent (UV/TiO2/RHS) in removal reactive red 198 dye from synthetic aqueous solutions. The removal of reactive red 198 dye was done in batch reactors with a volume of 250 ml using RHS deposited by titanium dioxide in the presence of a UV lamp. The effect of pH, immobilization of TiO2 on RHS adsorbent, contact time, nanoparticle mass and initial concentration of dye in removal efficiency were investigated. The results of this research showed that with an increase in pH and alkalinity of the solution, the removal efficiency declined. As the pH changed from 3 to 9, the removal efficiency in UV/TiO2/RHS, RHS adsorbent and UVC radiation declined from 75.25 to 27.87, 8.37 to 3.4, and 16.62 to 3.25%, respectively. The maximum dye removal efficiency obtained by UV/TiO2/RHS was as large as 87.5% under pH=3, contact time of 60 min, nanoparticle mass of 1 g/L, and 25 mg/L concentration of the reactive red 198 dye. Therefore, the rice husk silica as a natural adsorbent in combination with (TiO2/UV) can be used as an effective method for removal reactive red of aqueous solutions on a larger scale by optimizing the parameters affecting the removal efficiency. تفاصيل المقالة -
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13 - Highly Porous Bi(III) Modified Rice Husk Silica Photocatalyst for the Photocatalytic Removal of Cationic Methylene Blue
Normawati Jasni Anwar Iqbal N. H. H Abu Bakar Dede Heri Yuli Yanto Hor Jia Yi Noor Haida Mohd Kaus Mohd Norazmi Ahmad Sri MulijaniA series of bismuth-silicate photocatalysts were synthesized via the sol-gel method for photodegradation of methylene blue (MB) under sunlight irradiation, utilizing rice husk ash as a silica precursor. The scanning electron microscopy/energy dispersive X-ray (SEM/EDX) أکثرA series of bismuth-silicate photocatalysts were synthesized via the sol-gel method for photodegradation of methylene blue (MB) under sunlight irradiation, utilizing rice husk ash as a silica precursor. The scanning electron microscopy/energy dispersive X-ray (SEM/EDX) analysis detected Bi content in 3-10 wt% range. Furthermore, it can be seen that the porosity decreased as the Bi concentration increased. The N2 adsorption-desorption analysis indicates the presence of mesopores with an average diameter of 297-554 Å with Brunauer–Emmett–Teller (BET) surface area of 5.6-30.5 m2/g. The photocatalyst with a Bi concentration of 4 wt% (RHSBi-A2) was the most active in the photodegradation of MB; the removal reached 90% within 4 h. The photodegradation is proposed to be driven by superoxide ( ), hydroxyl (•OH) radicals, and hole (h+) based on the valence band (VB) and conduction band (CB) potentials. The porous silica framework is proposed to act as an electron reservoir, allowing better MB adsorption and enhancing light absorption. تفاصيل المقالة -
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14 - Lactation Performance of Nili-Ravi Buffaloes Fed Alkali Treated Rice Husks
N.A. Tauqir F. Ahmad A. Faraz I.M. Gorsi N. Mujahid A. AsgharA feeding trial was carried out using 20 lactating Nili-Ravi buffaloes, divided into 4 groups (n=5) having similar parity and milk production to examine the influence of 2% NaOH treated rice husk on their milk yield and composition, blood metabolites and nutrient digest أکثرA feeding trial was carried out using 20 lactating Nili-Ravi buffaloes, divided into 4 groups (n=5) having similar parity and milk production to examine the influence of 2% NaOH treated rice husk on their milk yield and composition, blood metabolites and nutrient digestibility. Four iso-nitrogenous (14.0% crude protein (CP)) and iso-caloric (metabolizable energy (ME) 2.5 Mcal/kg) rations, containing zero (control), 10%, 20% and 30% rice husk, were formulated. Buffaloes were individually fed the diets ad libitum. Ten kg of available green fodder (Trifolium alexandrinum, berseem) was also offered to each animal. Feed consumed was noted daily by subtracting refusals. Milking was twice a day with the yield being recorded. Milk samples were analyzed for fat, solids-not-fat, total solids and protein. A digestibility trial was conducted at the end of the study for seven days using three animals from each group. Milk yield and composition was similar across the treatments. Nutrient digestibility of dry matter, crude protein, crude fiber and ash increased linearly with increasing levels of treated rice husk, but differences were non-significant (P>0.05). Similarly, changes in blood metabolites also not significantly affected by the treatments. It can be concluded that treatment of rice husks with a low level of NaOH has no harmful effect, so can be used in the formulation of diets for lactating buffaloes. تفاصيل المقالة -
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15 - Quality Characteristics of Chevon Sausage Obtained from Goats Fed a 50% Inclusion Level of Melon (<i>Colocynthis citrillus</i>) Husk and Palm (<i>Elaeis guineensis</i>) Oil Slurry
K.A. Sanwo S.O. Iposu J.A. Adegbite S.S. Abiola O.A. FanimoA study was undertaken to determine effect of nutritional value of Melon husk (MH) and Palm oil slurry (POS) on quality of chevon obtained from West African Dwarf (WAD) goats fed finishing diets as follows: diet 1(0% MH, 0% POS); diet 2 (50% MH, 0% POS); diet 3 (0% MH, أکثرA study was undertaken to determine effect of nutritional value of Melon husk (MH) and Palm oil slurry (POS) on quality of chevon obtained from West African Dwarf (WAD) goats fed finishing diets as follows: diet 1(0% MH, 0% POS); diet 2 (50% MH, 0% POS); diet 3 (0% MH, 50% POS) and diet 4 (50% MH, 50% POS), along with Panicum maximum as basal diet for all dietary treatment groups. After 60 days of feeding, eight goats (two goats per treatment) were slaughtered and muscles from the forelegs were used to produce chevon sausages, respectively. Proximate composition, sensory evaluation, cooking and refrigerated weight losses of sausages were determined. All data generated were analyzed as a oneway analysis of variance in a completely randomized design using SPSS statistical package. The study showed that values obtained for dry matter contents of the diets ranged from 89.53% to 89.81%. Cooking weight loss of the chevon sausages showed no significant (P>0.05) difference but refrigerated weight loss was lowest for sausages from goats fed diet 3 at 0.37%, with a high crude fat content of 13.30%. In conclusion, palm oil slurry reduced refrigerated weight loss in chevon sausage while organoleptic properties of chevon sausage, such as flavor, juiciness, saltiness e.t.c. were not influenced by dietary treatments. تفاصيل المقالة -
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16 - Effect of Litter Material and Elevated Platform Enrichment on Behaviour and Welfare of Broiler Chickens in Closed-House System
K.K.S. Kapuarachchi R.M.A.S. Bandara T.I.G. PrabashwariThe present study assessed the effect of litter materials (paddy husk and sawdust) and elevated platform enrichment on welfare (foot pad dermatitis (FPD), hock burns, plumage cleanliness, behaviours, litter quality, and body weight of the broiler chickens living in the أکثرThe present study assessed the effect of litter materials (paddy husk and sawdust) and elevated platform enrichment on welfare (foot pad dermatitis (FPD), hock burns, plumage cleanliness, behaviours, litter quality, and body weight of the broiler chickens living in the cooling pad area of a closed house. A total of 320 Indian River broiler chicks were randomly allocated to four treatments: paddy husk with an elevated platform, paddy husk with no elevated platform, sawdust with an elevated platform, and sawdust with no elevated platform with four replicates for each treatment (n=20). Behaviour of the birds was assessed by scan sampling methods. Welfare indicators were assessed by using a scoring system. Data were analyzed using a generalized linear mixed model and Kruskal-Wallis tests. There was no effect of litter material on the prevalence of FPD (P>0.05). Elevated platforms reduced the severity of FPD in the birds in both litters (P<0.05). The birds reared in sawdust regardless of elevated platforms, showed higher (P<0.05) scores for hock burns. Litter quality was lower in sawdust, irrespective of the elevated platforms (P<0.05). There was no effect of the elevated platform on litter quality, hock burns, plumage cleanliness, and behaviours of the birds. A higher frequency of dust bathing was observed in paddy husks (P=0.014). Litter material or elevated platform did not affect body weight of the birds. Results revealed that the provision of elevated platforms and paddy husk litter material enhanced the welfare of broiler chickens in the closed-house system. تفاصيل المقالة -
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17 - Mitigation methane emission in paddy field utilizing biosilica of rice husk
John Bimasri Dedik Budianta Muhammad Harun Marsi -The increasing of paddy production give an environmentally impact, because paddy cultivation contributes 46.2% of the total greenhouse gas emissions from agriculture. The paddy cultivation emission amounted to 76% of methane. Meanwhile, the grain produced by paddy consi أکثرThe increasing of paddy production give an environmentally impact, because paddy cultivation contributes 46.2% of the total greenhouse gas emissions from agriculture. The paddy cultivation emission amounted to 76% of methane. Meanwhile, the grain produced by paddy consists of 16.3% to 28% husk with 18 to 22.3% silica. Silica contained in the soil can increase the root oxidation power of paddy, thus it will reduce methane emissions. The objective of this research was to evaluate the reduction of methan emissiom from paddy field by using silica from rice husk. This research used experiment with randomized block design and has eight treatments with three repetitions. The dose of biosilica is equivalent with 200 kg ha-1 of ameliorant in the form of ash, biochar, and compost. The methane analysis was carried out at 1, 5, 8, 12, and 15 weeks after planting. The methane was analized by GC with FID. The result of the research show that the ash produced from rice husk is the best single source of biosilica in paddy soil that can reduce methane emissions by 80.75%. The composition of ash, biochar, and compost (1:1:1) can increase the paddy growth and paddy production as well as reduce methane emissions effectively. The reduction of methane emission by giving silica into the soil is happened through the dissolved silica mechanism. The dissolved silica causes the increasing of pH and the root oxidation power of paddy. تفاصيل المقالة -
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18 - A mathematical model for optimization of strength of concrete: A case study for shear modulus of Rice Husk Ash Concrete
O.S OgahRice Husk Ash (RHA) is natural Pozzolan containing reactive silica and/or aluminum. When the material is mixed with lime in powdered form and in the presence of water, it will set and harden like cement. This work uses Osadebe’s optimization model to optimize the أکثرRice Husk Ash (RHA) is natural Pozzolan containing reactive silica and/or aluminum. When the material is mixed with lime in powdered form and in the presence of water, it will set and harden like cement. This work uses Osadebe’s optimization model to optimize the shear modulus of concrete made from RHA. The strengths predicted by the model are in good agreement with their corresponding experimentally obtained values. With the model, any desired strength of hardened concrete, given any mix proportions, is easily evaluated. The average Poisson ratio and mean shear strength for the concrete are found to be 0.26 and 5.5 N/mm2 respectively. تفاصيل المقالة -
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19 - تاثیر تنش خشکی و محلول‌پاشی آهن و روی بر عملکرد و اجزای عملکرد آفتابگردان در کشت دوم
حامد جوادیبه منظور بررسی اثر تنش خشکی و محلول‌پاشی آهن و روی بر عملکرد و اجزای عملکرد آفتابگردان در کشت دوم آزمایشی در مزرعه تحقیقاتی مرکز آموزش جهاد کشاورزی بیرجند در سال 1393 به صورت اسپلیت پلات در قالب طرح بلوک‌های کامل تصادفی با سه تکرار انجام شد. فاکتورهای مورد مطالعه شامل ت أکثربه منظور بررسی اثر تنش خشکی و محلول‌پاشی آهن و روی بر عملکرد و اجزای عملکرد آفتابگردان در کشت دوم آزمایشی در مزرعه تحقیقاتی مرکز آموزش جهاد کشاورزی بیرجند در سال 1393 به صورت اسپلیت پلات در قالب طرح بلوک‌های کامل تصادفی با سه تکرار انجام شد. فاکتورهای مورد مطالعه شامل تیمار آبیاری (آبیاری کامل تا پایان دوره رشد، مطابق نیاز گیاه و قطع آبیاری در مرحله پر شدن دانه) به عنوان فاکتور اصلی و محلول‌پاشی کود ریزمغذی (شاهد، آهن، روی و آهن+روی) به عنوان فاکتور فرعی بودند. نتایج نشان داد که اثر تنش خشکی بر صفاتی مانند ارتفاع بوته، قطر طبق، تعداد برگ در شروع غنچه دهی و رسیدگی، وزن خشک طبق، شاخص سطح برگ در شروع غنچه دهی و رسیدگی، تعداد دانه در طبق، وزن هزار دانه، عملکرد دانه، عملکرد کاه و کلش، عملکرد بیولوژیک و نسبت دانه به پوست معنی‌دار نبود، اما تنش خشکی باعث کاهش شاخص برداشت گردید. تنش در مرحله پرشدن دانه 29/18 درصد شاخص برداشت را نسبت به شاهد کاهش داد. اثر محلول‌پاشی کودهای ریز مغذی نیز برتمامی صفات مورد مطالعه (بجز تعداد برگ در مرحله رسیدگی) معنی‌دار نبود. محلول پاشی با آهن+روی باعث افزایش تعداد برگ در مرحله رسیدگی نسبت به سایر تیمارها گردید. همچنین اثر متقابل تنش خشکی× محلول‌پاشی کود ریزمغذی بر صفات مورد مطالعه معنی‌دار نبود. با توجه به نتایج حاصل از این تحقیق قطع آبیاری در مرحله پر شدن دانه و محلول‌پاشی کود ریزمغذی آهن و روی بر عملکرد دانه در کشت دوم آفتابگردان در منطقه بیرجند تاثیری ندارد. تفاصيل المقالة -
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20 - The Investigation and Evaluation of Some Important Mechanical Tests for the Consumed Varieties of Persian Walnut
A.R. Makarichian G.R. CheginiRemoving the green husk and drying walnut are one of the most important steps in post-harvest processing of walnut. Therefore, it is need to precisely identify a walnut’s shell. Physical and mechanical properties of shell in the four Persian walnut cultivars/genot أکثرRemoving the green husk and drying walnut are one of the most important steps in post-harvest processing of walnut. Therefore, it is need to precisely identify a walnut’s shell. Physical and mechanical properties of shell in the four Persian walnut cultivars/genotypes were studied. This study investigated the mechanical properties of a walnut’s husk and calculated the required energy in the process of shearing, penetrating and bruising for four walnut cultivars/genotypes (K72, Z67, Pedro, Serr). This was done by a texture analyzer instrument. Required energy to perform each of these tests were given in terms of the maximum and minimum values. The averaged results were so that the maximum amount of Krammer shear test belonged to K72 variety and the minimum of that belonged to Pedro variety. Penetration’s test data also indicated that the maximum amount in four available varieties was Pedro and the minimum value was suitable for Z76. Also, in the bruising test, Serr variety had the maximum value of required energy and Z76 variety had the minimum energy requirement. تفاصيل المقالة -
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21 - Evaluation of a Walnut Huller
G.R. Chegini A.R. MakarichianWalnut is one of the high yielding crops in horticultural production, and establishment of walnut orchards is growing. Yet despite Iran’s being the second largest producer of walnuts in the world, this country does not play a significant role in walnut export. Thi أکثرWalnut is one of the high yielding crops in horticultural production, and establishment of walnut orchards is growing. Yet despite Iran’s being the second largest producer of walnuts in the world, this country does not play a significant role in walnut export. This gap is most affected by the need to mechanize the harvesting process. This case is more understandable when can construct a new device with greater efficiency in comparison of the existing mechanical systems. In this article, a walnut huller built on the Abouraihan campus of the University of Tehran is evaluated, with Rotational speed, time and brush distance being optimized to make the best quality of hulling process. The results indicate that increasing the rotational speed, increases the amount of walnuts hulled but that the percentage of damaged nuts also increases. If, at a constant rotational speed, the distance between abrasive brushes is reduced, the amounts of nuts hulled and damaged are raised but the degree of hulling is greater than degree of injury. Also, if the distance between abrasive brushes and the rotational speed are decreased, the peeling rate is increased while the damage rate is decreased. تفاصيل المقالة -
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22 - Comparative Evaluation of Cadmium Ion Uptake byWastes Generated from Zea mays
Chidi DuruThe removal of cadmium ions from aqueous solution by Zea mays husk (HK), stalk (SK), cob (CB) and seed chaff (SC) which are wastes generated after harvesting or processing this cereal were studied and compared. Batch adsorption studies were utilized to decide the impact أکثرThe removal of cadmium ions from aqueous solution by Zea mays husk (HK), stalk (SK), cob (CB) and seed chaff (SC) which are wastes generated after harvesting or processing this cereal were studied and compared. Batch adsorption studies were utilized to decide the impact of different parameters on the process. Cadmium ion uptake by the adsorbents increased with increase in pH from 3 – 6, with HK and CB showing a steady increase as pH changed. The removal efficiency of all the adsorbents increased with adsorbent dose. However, after 0.4 g load of adsorbent, the removal efficiency of SC became independent of adsorbent load. The maximum adsorption capacity of HK, SK and CB was attained in 12 minutes while SC reached this point in 9 minutes. The adsorption equilibrium data for all the adsorbents fitted well in the Freundlich isotherm model. The adsorption intensities of all the adsorbents from this model were greater than 1, and indicated that metal ion adsorption by these adsorbents were favourable physical processes. The rate of cadmium ion adsorption onto the adsorbents was better explained by the pseudo second-order kinetic model. The calculated equilibrium adsorption capacity of HK (16.36 mg/g) and SK (13.51 mg/g) showed that they had potentials for commercial application in the remediation of cadmium ion polluted water. تفاصيل المقالة -
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23 - Kinetic and Equilibrium Studies for Dye Adsorption onto Sugarcane Bagasse and Rice Husks
Noorul Hudai Abdullah Nur Atikah Abdul Salim Baizura Binti Hamid Muhammad Azri Nizamdin Muhammad Fauzul Mubarak Ahmad Fadhil Nurhana Syahira Azman Nur Farhan Zon Masiri Kaamin Amir Khan Suwandi Noraziah Ahmad Zainab Mat Lazim Maria Nuid Nur Azmira ZainuddinThe textile industry discharges large quantities of highly colored wastewater from industrial processes using chemical components. Many dyes are designed to be chemically stable so that they are difficult to decolorize due to their complex structure and synthetic origin أکثرThe textile industry discharges large quantities of highly colored wastewater from industrial processes using chemical components. Many dyes are designed to be chemically stable so that they are difficult to decolorize due to their complex structure and synthetic origin. The dye waste is subsequently released directly to water bodies during the textile finishing process. This improper released has adverse effects on the environment and may reduce photosynthesis in aquatic plants. Even though adsorption techniques have been widely used to remove textile dye from waters, the kinetic models used to describe the adsorption of textile dye onto a porous material is still not yet fully understood. This study investigated different applications of absorbent from sugarcane bagasse (SB) and rice husks (RH) in removing color from aqueous solution and the application of kinetic model for adsorption of color from aqueous solutions onto SB and RH. A batch study was carried out under various mass of adsorptions and contact time with constant with the initial concentration of aqueous solution was 400ADMI. The data obtained from batch experiments showed that the removal of RH (93%) was more efficient than SB (49%). This study also advanced the understanding on the kinetic adsorption study of RH and SB to prove that the adsorbents have potential to reduce dye from synthetic solution. The contribution of this study in the removal of significant dye pollutants from industrial wastewater will require future assessment in a prospective wastewater treatment facility setting. تفاصيل المقالة
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