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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Rehabilitation in Civil Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Mechanical properties,High strength,Cementitious Composites,Impact Resistance
- چکیده:
- چکیده انگلیسی: Cementitious composites are one of the most consumed construction materials in the world. The use of cementitious composites is increasing due to their special characteristics. The behavior of high strength cementitious composites is improved by increasing the fiber percentage. In the present paper, the effects of steel microfibers and polypropylene fibers on mechanical properties and impact resistance of high strength cementitious composites are investigated. The percentage of fibers used in the study was 0, 0.5, and 1.5% in seven separate and three combined mix designs. Experiments were carried out on 120 specimens in 10 mix designs. Compressive strength, tensile strength, flexural strength, and dynamic impact tests were carried out on 10 mix designs manufactured in this research. The dynamic impact strength of the disc specimen was investigated by a drop hammer test machine with a capacity of 7500J. After testing the samples, it was shown that using a high percentage of steel and polypropylene fibers reduces the compressive strength and increases tensile strength, flexural strength, and impact strength. The effects of steel microfibers on the reduction of the crush displacement resulting from the dynamic impact were higher than that of polypropylene fibers.
- انتشار مقاله: 29-12-1397
- نویسندگان: Ahmad Dalvand,Ebrahim Sharififard,Fereydoon Omidinasab
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Herbal Drugs
- نوع مقاله: Journal Article
- کلمات کلیدی: essential oil,Thymus fedtschenkoi,Yazd,Carvacrol,Thymol
- چکیده: مقدمه و هدف: آویشن گیاهی است بوتهای، دایمی و معطر که در بعضی از مناطق ایران به صورت خودرو رویش دارد. این تحقیق به منظور تعیین و معرفی اکسشنهای برتر آویشن قره باغی(Thymus fedtschenkoi) کشت شده از لحاظ کمیت و کیفیت اسانس اجرا شد. روش تحقیق: این تحقیق در ایستگاه تحقیقات گیاهان دارویی استان یزد با مختصات طول جغرافیایی 49 31 ، 53 شمالی و عرض 54 15 27 شرقی به ارتفاع 1209 متر از سطح دریا در منطقه گردفرامرز شهر شاهدیه یزد به اجرا در آمد. بذور 5 اکسشن آویشن قره باغی جمع آوری شده از استانهای آذربایجان غربی، سمنان و زنجان در سال 1389 در جیفیپات کشت گردید. در سال دوم از سرشاخههای گیاه هنگام 50 درصد گلدهی برداشت شده و پس از خشک کردن در سایه به روش تقطیر با آب اسانسگیری انجام شد. پس از تعیین راندمان اسانس نسبت به وزن خشک، بوسیله کروماتوگرافی گازی و کرومانوگرافی گازی متصل به طیف سنجی جرمی تجزیه و شناسایی اسانسها صورت گرفت. نتایج و بحث: از نظر بازده اسانس بیشترین درصد اسانس در زمان گلدهی گیاه مربوط به اکسشنTF3 با منشاء استان سمنان (2/4%) و کمترین میزان آن مربوط به اکسشن TF5 با منشاء استان آذربایجانغربی (8/0%) بود. بیشترین میزان تولید اسانس در هکتار مریوط به اکسشنTF3 با (kg/ha8/32) و کمترین میزان به اکسشنTF5 با kg/ha)3) تعلق داشت. حداکثر میزان ترکیبات عمده اسانس تیمول، پارا-سیمن، کارواکرول، بورنئول، ترپینئول، گاما-ترپینن، 1و8 سینئول، ای- کاریوفیلن و لینالول به ترتیب مربوط به اکسشنهای TF1(1/70%)، TF5(2/20%)، TF4(1/18%)، )TF44/10%)، TF3(5/4%)، TF5(1/4%)، )TF46/3%)، TF33/3%)، TF5 (1/3%) بود. با در نظر گرفتن بازده اسانس، میزان تولید و ترکیب متشکله اسانس اکسشن TF3با منشاء استان آذربایجان غربی با 2/4 درصد اسانس و میزان تولید 8/32 کیلوگرم اسانس در هر هکتار و 33/66 درصد تیمول به عنوان اکسشن برتر در بین اکسشنهای کشت شده معرفی میگردد. توصیه کاربردی/ صنعتی: با توجه به اینکه اکسشن TF3 دارای عملکرد، بازده اسانس و درصد تیمول بالا میباشد جهت کشت و ترویج در مناطق آب و هوایی مشابه توصیه میگردد.
- چکیده انگلیسی: Background & Aim: The genus Thymus belonging to the family of lamiaceae and consist over 215 different species throughout the word. Eighteen species grow naturally in Iran of which four species are endemic. Experimental: This reseach has been carried in medicinal plants research station in Yazd province with the coordinates of longitude and latitude 55 31 49 northly, 27 15 54 east to heigh of 1209 meters above Sea level in the region Gerdefaramarz city of Yazd shahedial. In order to in 2011 year seeds 5 accession of T. fedtschenkoi collected from West Azarbayejan, Semnan and Zanjan provinces, were planted in jifypot. The aeril parts of plants were collected 50% flowering stage and then were dried in shadow and hydro– distilled for obtaining their essential oil. Analysis and identification of chemical composition of the oil were performed by GC and GC/MS. Results & Discussion: The highest amount of oil yield respectively were related to accession TF3 from Semnan (4.2%), and lowest was related to accession TF5 from West Azarbayejan(0.8%). The highest amount of oil production respectively was related to accession TF3 (32/8kg/ha) and lowest was related to TF5 (3kg/ha). Results showed that maximum compositions of essential oil Thymol, P-cymen, carvacrol, borneol, Terpineol, γ-terpinene, 1,8 cineol, E-caryophyllene and linalool, respectively TF1 (70/1%), TF5 (20/2%), TF4 (18/1%), TF4 (10/4%), TF3(4/5%), TF5 (4/1%), TF4 (3/6%), TF3 (3/3%) and TF5 (3/1%) Generally, with regard to oil yield, oil production and main composition of essential oil accession TF3 with 4/2% and rate of oil production 32/8kg/hectare and 66/3% Thymol was selected as superior accession. Recommended applications / industries: Since the accession TF3 yield, oil yield and thymol is high. for planting in the same climate zones is recommended.
- انتشار مقاله: 10-01-1394
- نویسندگان: Abas Zarezadeh,Mehdi Mirza,Ebrahim Sharifi Ashour Abadi,Ali Mirhossaini,Mohammad Reza Arabzadeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Natural Resources Research
- نوع مقاله: Journal Article
- کلمات کلیدی: essential oil,Seed yield,Pimpinella affinis,Planting date,limonene,Trans α-bergamotene
- چکیده:
- چکیده انگلیسی: In order to investigation the effects of seed origin and planting date on yield and essential oil of Pimpinella affinis, a field experiment was carried out in Alborz Research Center in 2007. This experiment was performed under factorial in the base of (RCBD) with three replications. The treatments were included locations of seeds collection and planting dates. Essential oils were extracted from different parts in all experimental units separately. The results showed that the effects of locality on seed yield, inflorescence oil percentage, seed oil percentage, seed oil yield and limonene percentage had significant difference with other treatments. Effects of planting date on seed yield, Inflorescence oil percentage and seed oil yield was significant different with others. Interaction between locality and planting date on height, stem plus leaf oil percentage, Inflorescence oil percentage, seed oil percentage, seed oil yield, limonene percentage and trans α-bergamotene percentage were significant different. The major compositions of Tehran chemotype were limonene (>83%) and geijerene and the major composition of Mazandaran chemotype was trans α-bergamotene (>91%). As a result, seed origin from Mazandaran is recommended to cultivation due to presence of trans α-bergamotene in essential oils, and Tehran seed origin for its seed oil yield and biomass.
- انتشار مقاله: 23-02-1391
- نویسندگان: Fatemeh Askari,Fatemeh Sefidkon,Ebrahim Sharifi Ashorabadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Industrial Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: EOQ,Acceptance sampling,Destructive testing,Inspection,Perishable items
- چکیده:
- چکیده انگلیسی: Now a days, management and control of perishable inventories is important in many units and industrial enterprises. Basically perishable inventory management and control is more complex and challenging than inventories with unlimited lifetime. Hence determining the optimal inventory policies for these products is very important. In this paper, the optimal inventory policy for perishable items given to the a single acceptance sampling plan with destructive testing and inspection errors is adopted .After developing a model for the problem and obtaining the objective function, first an exact solution and a simple and efficient algorithm to find the optimal values is proposed. Then, the model will be validated with a numerical example and senility analysis.
- انتشار مقاله: 22-07-1394
- نویسندگان: Javad Hasanpour Rodbaraki,Ebrahim Sharifi
- مشاهده