Effect of growth parameters on structural and optical properties of CdS nanowires prepared by polymer controlled solvothermal route     

Iraj Kazeminezhad  Negar Hekmat  Alireza Kiasat 《Fibers and Polymers》2014,15(4):672-679

Cadmium sulfide nanowires were successfully obtained via a poly (ethylene glycol)-assisted solvothermal route. In this procedure, cadmium nitrate and thiourea were used as Cd and S sources, respectively, and polyethylene glycol 400 was used as an inducing soft template to control the one-dimensional growth of CdS nanostructures. The effects of different growth parameters in the solvothermal process such as type of the solvents, reaction time, and temperature on the morphology, structural and optical properties of the products were investigated. The provided structures were characterized by X-ray diffractometery, scanning electron microscopy, and UV-visible absorption spectroscopy. The results show that the as-prepared samples have hexagonal phase and grow into long nanowire shape with increasing the reaction time, temperature and volume ratios of ethylenediamine (en) to H₂O. Uniform sized nanowires with the average diameter of 75 nm and the average length of 2.5 µm were obtained using ethylenediamine solvent at 170 °C for 3 days.  相似文献   

Genetic analysis of flowering and maturity time in high latitude spring wheat     

Muhammad Iqbal  Alireza Navabi  Donald F. Salmon  Rong-Cai Yang  Brenda M. Murdoch  Steve S. Moore  Dean Spaner 《Euphytica》2007,154(1-2):207-218

Due to the short growing season in the high northern latitudes, the development of early maturing spring wheat (Triticum aestivum L.) cultivars is important to avoid frost damage which can lower production and quality. We investigated earliness of flowering and maturity, and some associated agronomic traits, using a set of randomly selected high northern latitude adapted spring wheat cultivars (differing in maturity) and their F₁ and F₂ crosses made in a one-way diallel mating design. The parents, and their F₁ and F₂ crosses were evaluated under field conditions over 2 years. Anthesis and maturity times were controlled by both vernalization response and earliness per se genes, mainly acting additively. Non-additive genetic effects were more important in controlling grain fill duration, grain yield and plant height. Additive × additive epistatic effects were detected for all traits studied except time to anthesis. Segregation analyses of the F₂ populations for time to anthesis indicated the presence of different vernalization response genes. Molecular genetic analyses revealed the presence of Vrn-A1 and Vrn-B1 genes in the parental cultivars. Narrow-sense heritability was medium to high (60–86%) for anthesis and maturity times but low to medium (13–55%) for grain fill duration, plant height and grain yield. Selection for early flowering/maturity in early segregating generations would be expected to result in genetic improvement towards earliness in high latitude spring wheats. Incorporation of the vernalization responsive gene Vrn-B1 in combination with vernalization non-responsive gene Vrn-A1 into spring wheats would aid in the development of early maturing cultivars with high grain yield potential for the high latitude wheat growing regions of the northern hemisphere.  相似文献   

Role of Raf in vascular protection from distinct apoptotic stimuli     

Alavi A  Hood JD  Frausto R  Stupack DG  Cheresh DA 《Science (New York, N.Y.)》2003,301(5629):94-96

Raf kinases have been linked to endothelial cell survival. Here, we show that basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) differentially activate Raf, resulting in protection from distinct pathways of apoptosis in human endothelial cells and chick embryo vasculature. bFGF activated Raf-1 via p21-activated protein kinase-1 (PAK-1) phosphorylation of serines 338 and 339, resulting in Raf-1 mitochondrial translocation and endothelial cell protection from the intrinsic pathway of apoptosis, independent of the mitogen-activated protein kinase kinase-1 (MEK1). In contrast, VEGF activated Raf-1 via Src kinase, leading to phosphorylation of tyrosines 340 and 341 and MEK1-dependent protection from extrinsic-mediated apoptosis. These findings implicate Raf-1 as a pivotal regulator of endothelial cell survival during angiogenesis.  相似文献   

Nutrition Management and Farm’s Age Affect Saffron Daughter Corms Behavior,Nutrients Uptake and Economic Water and Fertilizer Use Efficiency: A Large Scale On-farm Experiment in Torbat Heydarieh,Iran     

Alireza Koocheki  Seyyed Mohammad Seyyedi 《Communications in Soil Science and Plant Analysis》2020,51(9):1161-1183

ABSTRACT

Evaluation of the relationships between nutritional patterns and farms’ age with the behavior of saffron (Crocus sativus L.) daughter corms based on farmers’ management (on-farm) can be crucial in improving saffron sustainable yield. Furthermore, in commercial saffron production, especially in small farms, the purchased water and fertilizers are the basis of sustainable saffron profitability, hence, recognizing the relationships between economic water use efficiency (EWUE) and economic fertilizer use efficiency (EFUE) can be important. An on-farm experiment was conducted on a large scale based on farmers’ management in Torbat Heydarieh, Iran. The farms’ age (1–6 years old) and fertilizers management approaches (organic, mineral and integrated) were considered as the first and second factors, respectively. Large-sized daughter corms number and weight and corms N and P content increased with increasing farms’ age from 1 to 4 years old. However, these parameters decreased with increasing farms’ age from 4 to 6 years old. Irrespective of saffron farms’ age, the minimum large-sized daughter corms number and weight were observed when mineral fertilizer management was practiced. By contrast, the maximum values were related to integrated fertilizer management. In each type of fertilizer management, EWUE and EFUE (based on large-sized daughter corms monetary value) increased with increasing farms age from 1 to 4 years. However, increase in farms age from 4 to 6 years caused a significant reduction in mentioned indices. Overall, if high-quality saffron corm production is needed, corms should be harvested in the fourth year to gain the maximum yield and profit.  相似文献   

Monitoring of the fermentation media of citric acid by the trimethylsilyl derivatives of the organic acids formed     

Ghassempour A  Nojavan S  Talebpour Z  Amiri AA  Najafi NM 《Journal of agricultural and food chemistry》2004,52(21):6384-6388

In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method.  相似文献   

Foliar application of iron,zinc, and manganese nano-chelates improves physiological indicators and soybean yield under water deficit stress     

Mohammad Saeed Vaghar  Saeed Sayfzadeh  Hamid Reza Zakerin  Soheil Kobraee  Sayed Alireza Valadabadi 《Journal of plant nutrition》2020,43(18):2740-2756

Abstract

To investigate the effect of foliar application of nano-chelates of iron, zinc, and manganese subjected to different irrigation conditions on physiological traits, and yield of soybean (cultivar M9), a split plot experiment was conducted in a completely randomized block design with three replications in two crop years (2016–2017). The main plot included four levels of irrigation (I): full irrigation (I ₁), irrigation withhold at flowering stage (I ₂), irrigation withhold at podding stage (I ₃), and irrigation withhold during the grain filling period (I ₄). Also, the subplot included eight levels of foliar application with Fe, Zn, Mn, Fe?+?Zn, Fe?+?Mn, Zn?+?Mn, Fe?+?Zn?+?Mn nano-chelates, and distilled water (control). The results of combined analysis of variance suggested that the effect of irrigation and foliar application of nano-chelate was significant on all traits. Water deficit stress significantly reduced the grain yield. The minimum numbers of pods per plant, number of grains per plant, 100-seed weight per plant, leaf area index, leaf chlorophyll concentration, total dry weight of plant, and the grain yield were obtained by irrigation withhold at podding stage. Foliar application of combined nano-chelates increased the soybean resistance against water shortage more considerably than the separate consumption of these elements. Under drought stress in podding stage, the application of Fe?+?Zn led to the highest yield with a mean of 2613.84?kg ha^?1 where this increase was 61.1% higher than control.  相似文献   

基于COI基因的入侵物种旧金山卤虫遗传多样性与遗传分化研究     

付春正  王晖  Alireza Asem  郭慧芳  钱彬彬  刘文茹  沈春阳 《河北渔业》2022,(2):1-6,32

伴随着中国水产养殖业的快速发展,原产美国的旧金山卤虫(Artemia franciscana)被引入至我国渤海湾地区.为研究旧金山卤虫被引入中国后其基因组遗传多样性改变情况,本研究利用COI线粒体分子标记,评估旧金山卤虫在非原生栖息地,即唐山曹妃甸南堡镇(渤海湾,河北省)定殖的旧金山卤虫的遗传多样性现状.研究分析发现:...  相似文献   

Evaluation of the correlation between serum biochemical values and liver ultrasonographic indices in periparturient cows with different body condition scores     

Rafia S  Taghipour-Bazargani T  Asadi F  Vajhi A  Bokaie S 《American journal of veterinary research》2012,73(6):830-837

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Effect of mastitis during the first lactation on production and reproduction performance of Holstein cows   总被引：1，自引：0，他引：1  

Heravi Moussavi A  Danesh Mesgaran M  Gilbert RO 《Tropical animal health and production》2012,44(7):1567-1573

The aim of this study was to evaluate the effect of postpartum mastitis between first calving and subsequent conception on production and reproduction performance as well as culling of Holstein cows. A data set of 9,183 first lactation cows was used. Results showed that the first cumulative 100?days' milk production and the milk yield standardized to 305?days were affected by the interval from calving to first mastitis (P??0.05). Calving year, calving difficulty score, and cumulative first 60?days milk production had significant impacts on mastitis risk (P?相似文献   

Kinetics of transcription of infectious laryngotracheitis virus genes     

Mahmoudian A  Markham PF  Noormohammadi AH  Browning GF 《Comparative immunology, microbiology and infectious diseases》2012,35(2):103-115

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