首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   18篇
  免费   1篇
林业   3篇
  8篇
综合类   1篇
农作物   1篇
水产渔业   3篇
畜牧兽医   3篇
  2021年   1篇
  2020年   2篇
  2018年   3篇
  2017年   1篇
  2016年   3篇
  2014年   3篇
  2013年   2篇
  2012年   1篇
  2011年   1篇
  2010年   2篇
排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles.  相似文献   
2.
More than 50% of global soil organic carbon stocks are stored below 20 cm of soil depth capable of massively altering global C cycle and climate. However, subsoil C dynamics are largely overlooked implicitly assuming that surface and subsoil C dynamics are similar. Here, we compared the soil C dynamics in surface and subsurface soil layers in response to nitrogen and maize leaf litter additions. Soils, sampled from 0 to 5, 15 to 35, 35 to 55 and 55 to 75 cm depths, were incubated at 25°C after adding litter, nitrogen (NH4NO3) or litter plus nitrogen. Soil respiration (C mineralization) was measured throughout the incubation period. Litter addition significantly increased C mineralization in all the soil layers. However, the soil CO2 release relative to control was more than twofold higher in 15–35 and 35–55 cm soil layers than the surface layer. Nitrogen additions significantly decreased C mineralization in 0–15 cm soil, increased in 35–55 cm and had minimal effects in the 15–35 and 55–75 cm layers. Different soil C dynamics in surface and subsurface soil layers found in our study contradict the general assumption that soil C dynamics may be treated similarly along different soil depths.  相似文献   
3.
In recent decades, ambient gaseous pollution has increased due to anthropogenic activities worldwide. The studies to evaluate the adverse effects of ambient pollutants on commonly grown food crops are still limited, especially in Asian countries like Pakistan. The present study was conducted to measure the ambient pollutants in different sites of Faisalabad and their impact on growth and yield of wheat, mung bean and peas. Plants were grown in pots and placed at three sites named as control (Wire house of Government College University, Faisalabad), low pollution (LP) (Farm Area of Ayub Agricultural Research Institute) and high pollution (HP) (GT Chowk, Faisalabad) sites. Results showed that ambient ozone (O3) concentration was highest at HP site followed by LP site and was below AOT40 in control site. Ambient pollutants caused foliar injury in crops and decreased plant height, leaf area, biomass and grain yield. Pollutants caused a reduction in photosynthetic pigments, stomatal conductance and net photosynthetic rate and grain protein contents in all three crops. In conclusion, the ambient O3 level was highest at HP site, this current O3 level and other pollutants decreased the growth and yield of important food crops.  相似文献   
4.
A study was conducted to determine the effect of macronutrients (NPK) in alleviating the adverse effects of simulated acid rain (SAR) on sunflower (Helianthus annuus L.). In addition to control (T0), three different treatments, i.e., SAR (HNO3) of pH 3 (T1), NPK (T2), and SAR + NPK (T3), were applied on two sunflower cultivars, i.e., FH-37 and FH-385. The experiment was set up in CRD (completely randomized design) with four replicates of each treatment. Chlorophyll a, b, total chlorophyll, carotenoids, ion contents (NPK), and gas exchange characters were determined. Acid rain remarkably reduced the chlorophyll pigments, NPK ionic content, photosynthetic rate, transpiration rate, and stomatal conductance, while an increase in internal CO2 concentration and water use efficiency was noted in both the cultivars. The mixture of NPK with SAR exhibited positive impact to lessen the toxicity caused by acid. Among cultivars, FH-385 showed better performance as compared to FH-37.  相似文献   
5.
Tropical Animal Health and Production - The current experiment was performed to find the potential effect of inorganic and organic forms of zinc (Zn) on growth, intestinal histomorphology, immune...  相似文献   
6.
ABSTRACT

The knowledge about heterosis breeding of achene yield in sunflower is known; however, dissection of the genetic components of achene yield and seed quality traits is limited. Therefore, the prescribe study was conducted using Line × Tester design to determine combining abilities, and about the maternal-and-paternal gene actions involved in achene yield and seed quality traits in 21 single cross hybrids. Significant mean differences for achene yield and seed quality traits were observed, with total attributed variation (R2?=?0.89). Principal component analysis (P?<?0.05) explained 92.6% variation and using factor analysis, we found factor 1 had primary variables (AW, AL, AT, HD, PH, PC, LA and OC) contributed 35.6% variation to achene yield. Combining ability analysis showed the positive general combining ability for E%, HD, PH, 100 AW and AYP in parental inbred lines, whilst, hybrids had positive specific combining ability for E%, HD, PH, 100 AW, DTF, DTM, OA, LA, OC and AYP. Females contributed significantly higher (P?<?0.05) for AYP, E%, HD, NWPH, PH, 100 AW, LA and OA than that of males. Two-way hierarchical clustering showed the most promising hybrid H5 (A-18?×?G-79) in Cluster V. The hybrid H5 also showed heterosis, heterobeltosis and commercial heterosis, therefore, genetic exploitation of H5 is highly desirable in future breeding to map QTLs/genes in arid/semi-arid zones and /or similar growing conditions to boost up yield and seed quality traits.  相似文献   
7.
Hemoplasmas are ubiquitous pleomorphic and epicellular bacteria detected in erythrocytes in several species. In Brazil, studies on hemoplasmas have not included information on occurrence, clinical signs, and risk factors in dogs. This paper investigates the occurrence of hemoplasmas in dogs, focusing on risk factors and clinical status. Conventional PCR for the four types of canine hemoplasmas was performed in 331 blood samples collected from dogs clinically treated at a teaching veterinary hospital. Of all samples, 17/331 (5.1%) were positive for Mycoplasma haemocanis and 6/331 (1.8%) were positive for a ‘Candidatus Mycoplasma haemominutum-like’ organism. Risk factors included the presence of vectors, old age, dog bite wounds, and neoplastic diseases. In the multivariate analysis, a 4.40 odds ratio in dogs with vector-borne diseases indicated risk for hemoplasmosis. There was correlation between hemoplasma infection and neoplastic disease, suggesting that neoplastic conditions are a risk factor for hemoplasma infection in dogs.  相似文献   
8.
Current study investigated the fermentative production of cell mass and crude protein using an axenic culture of the thermotolerant strain of Chlorella vulgaris grown mixotrophically in an illuminated 10-l glass bioreactor. The process was then upscaled to 1,000-l bioreactor. The organism supported maximum specific growth rate, crude protein volumetric productivity, and specific productivity of 1.2?day?1, 2.26?g?l?1?day?1, and 0.76?g?g?1?day?1, respectively, with urea as nitrogen source. Gibbs free energy, enthalpy, and entropy values for its formation were 74.3, 56. 2?kJ?mol?1, and ?59.1?J?mol?1?K?1, respectively, in both reactors and corresponded to those of thermotolerant organisms. Algal biomass grown in 10-l bioreactor contained 0.52?±?0.03, 12.6?±?2.0, 60.0?±?4.5, 0.4?±?0.02, 4.5?±?0.2, 12?±?0.5, and 3.81?±?0.5% carotenoids, carbohydrates, crude protein, DNA, RNA, lipids, and total chlorophyll, respectively. Dry biomass supported good growth of fish larvae comparable with that on commercial diet.  相似文献   
9.
Fish Physiology and Biochemistry - The applications of exogenous hormones in different species for the induction of oocyte production, final oocyte maturation (FOM), and spawning for their...  相似文献   
10.
Sunflower was grown under saline media with or without vermicompost amendment and biogas slurry, the organic fertilizers. A randomized complete block design with five replications was used. Forty-five pots were divided in three sets comprising of 15 pots each. Out of 15 pots of each sets, five pots of each were subjected to different levels of saline water irrigation i.e. electrical conductivity (EC): 0.5, 4.8 8.6 dS/m). Amendments of vermicompost and biogas slurry have shown some reduction of sodium induced inhibitory effects. Analyses of fresh and dry weight of leaves, ions, amino acid, protein and nitrogen metabolism enzymes in leaves etc., have been undertaken with reference to above-mentioned treatments. Organic manure amendments improved growth yield, nitrate and protein content and decreased the amount of sodium (Na+), chloride (Cl?), ammonium and total amino acid under saline or non-saline condition. Activities of nitrogen (N)-assimilating enzymes i.e. nitrate reducatse (NR, EC 1.6.6.1), nitrite reductase (NiR, EC 1.6.6.4), glutamine synthetase (GS, EC 6.3.1.2) and glutamate synthase (NADH-GOGAT, EC 1.4.1.14) were enhanced to some extent irrespective to non saline or saline condition. Under salinity NADH-glutamate dehydrogenase (GDH, EC 1.4.1.2) activity was stimulated concomitantly with the increasing ammonium contents and proteolysis activity in the leaves and organic manure did not show a significant difference as compared to their respective control. With respect to salt stress, among the two above-mentioned organic manure, vermicompost showed better result in the entire studied parameter as compared to the biogas slurry.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号