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161.
Joonseok?KohEmail author Ik?Soo?Kim Sung?Soo?Kim Woo?Sub?Shim Jae?Pil?Kim 《Fibers and Polymers》2004,5(1):44-51
Three bi-functional reactive dyes such as Bis(vinylsulphone) type, Bis(monochlorotriazine) type and Bis(mononicotinotriazine) type were applied to regular viscose rayon and new regenerated cellulosic fiber (enVix®) which was prepared from cellulose acetate fiber by the hydrolysis of acetyl groups, and their dyeing properties and fastness properties were compared.enVix exhibited better dyeability and fastness than regular viscose rayon and these results were also explained by the differences in the supramolecular structure of these two fibers. 相似文献
162.
A.?V.?PashtetskyEmail author Yu.?V.?Plugatar O.?A.?Ilnitsky S.?P.?Korsakova 《Russian Agricultural Sciences》2018,44(2):131-136
The present studies have shown Laurus nobilis L. to be a drought tolerant species. When the plant was first subjected to dehydration, the rate of net photosynthesis decreased from Pn = (8–10) to –1 μmol/(m2 s) and to –3 μmol/(m2 s) during the second dehydration before it was subsequently irrigated. The rewatering on August 5 and August 8 promoted a sharp burst of this parameter, but the Pn value was restored to its original level only after August 8. Soil drought caused a drop in a rate of transpiration from 65–70 to 10 mg/(m2 s). Watering soil up to a 15% moisture level brought an increase in E = 25 mg/(m2 s), but only the second watering managed to fully restore it to the initial value. Apical growth of the plants was closely correlated with soil moisture. As the soil moisture was reduced to W = 15–5%, the terminal growth reached a saturation point and started to plateau. Watering the soil up to W = 15% promoted apical growth by 4 mm. Reducing soil moisture to W = 3–4% caused a complete cessation of the growth. Subsequent watering to W = 27–28% led to a gradual and complete recovery of turgor and an increase in the growth rate up to 6–8 mm per day. The surface response functions Pn = f(I, W) and E = f(I, W) allowed us to determine conditions and levels of potential maximums and boundaries of the areas of optimum photosynthesis and transpiration: optimum Pn = 8–9 μmol/(m2 s) with I = 900–1400 μmol/(m2 s) and W = 17–24% and the optimum E = 25–35 mg/(m2 s) with I = 1000–1400 μmol/(m2 s) and W = 16–24%. 相似文献
163.
The fabric used for intimate apparel is widely required to have excellent antibacterial and comfort performances. In order to improve its antibacterial ability, this paper studied chitosan-silver finishing on the cotton knitted fabric. The study indicates that the chitosan-silver attached to the fabric exhibits excellent antibacterial action against the typical bacteria of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu). The anti-bacterial mechanism of chitosan-silver against E. coli and S. aureu were investigated. To guarantee its prominent comfort performance, measurements were made on the finished fabric of its air permeability, water vapor transmission, hydrophily, surface friction and bending ability against the control fabric, which is currently used for intimate apparel. The antibacterial and comfort performances were compared between the tested fabrics. The results show that the air permeability and the hydrophily of the finished cotton fabric are significantly better than the control one, while the water vapor transmission, the surface friction and the adjustable rate remain similar to each other. The bending rigidity of the finished fabric is slightly better due to the attachment of chitosan within accepted threshold. The dual compounding theory of chitosan-silver proves to be useful for a higher synergistic effect of anti-bacteria, lower whiteness degradation and overall optimization of comfort performance. This dual compounding theory of chitosan-silver is valuable for improving antibacterial and comfort performances of intimate apparel. 相似文献
164.
The agricultural potentials of the floodplain soils of river Niger have been less exploited due to lack of information on their chemical and mineralogical characteristics. We studied five soil profiles within the floodplain to determine the levels of plant nutrients and relate them to their clay mineralogy and total element. The soils flooded for eight months of the year are low in pH and plant available nutrients while the dominant clay mineral is kaolinite. Kaolinite and interlayered vermiculite were negatively correlated with all the exchangeable bases, CEC and available P, indicating the negative contribution of these clay minerals to the plant nutrient reserve of these soils. Illite correlated positively with Na+ and K+ (r=0.51; 0.50), while smectite correlated significantly with Na, K, Ca and CEC. Also positive significant correlation existed between illite/smectite and Na+, K+, Mg2+, CEC and base saturation thus confirming the positive role of smectite and illite to the plant nutrient reserve in the soils. Kaolinite and CaO could be used for the prediction of exchangeable K (R2=0.62, 0.78 respectively). Although the level of nutrient cations are low, the depositional effect of the river and traditional cultivation practices can boost crop yield especially paddy rice. 相似文献
165.
Matthew?W.?MitchellEmail author Marcia?L.?Gumpertz 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(3):310-327
The Japanese RiceFACE (Free-Air CO2 Enrichment) project was a three-year investigation into the effect of elevated CO2 on rice. Four rings were built to emit elevated levels of CO2. The aim of the FACE system is to provide a level of CO2 enrichment 200 ppm above tmbient throughout the plot, without changing any other aspect of the microclimate within the plot.
However, there can be substantial spatial variation in the CO2 level from the center to the edges of the plots. One of our main objectives was to predict the seasonal mean levels of CO2 for multiple subregions within the plots. However, the dataset was very large and followed a nonnormal distribution. Furthermore,
the mean and variance were nonstationary. To overcome these difficulties daily means were used rather than individual measurements,
the mean was modeled with multiple covariates that varied over both time and space, and the variance was modeled as an increasing
function of the square of the distance from the center of the plot. A separable space-time covariance structure was used,
and estimation was performed using nonlinear methods, REML, and EGLS. Finally, cross-validation was used to assess the validity
of the model. 相似文献
166.
本文从拟南芥中克隆到基因At1g30210的全长读码框。多序列比对结果表明,在推导的氨基酸水平上,该基因编码的蛋白含有特征性的TCP保守结构域,与已知的玉米、金鱼草和水稻的TCP家族基因中都存在显著性的保守性。另外通过酵母单杂交实验证明该基因编码的蛋白在酵母体内具有转录激活功能。同时RT-PCR实验结果表明,该基因在拟南芥花组织中表达量相对较高,具有明显的组织表达特异性。花器官高表达转录因子的克隆将为研究TCP基因调控植物花发育和花形态建成提供新的物质基础。 相似文献
167.
Marcelo?C.?de?AlvesEmail author Fábio?M.?da?Silva Jair?Campos?Moraes Edson?A.?Pozza Marcelo?S.?de?Oliveira Júlio?C.?S.?Souza Luciana?S.?Alves 《Precision Agriculture》2011,12(1):18-31
The advent of geostatistics and geographical information systems has made it possible to analyze complex spatial patterns
of ecological phenomena over large areas in applied insect ecology and pest management. The objective of this study was to
use geostatistics to characterize the spatial structure and map the spatial variation of damage caused by the berry borer
(Hypothenemus hampei) and leaf miner (Leucoptera coffeella) in a coffee agroecosystem planted with the cultivar Catuai Vermelho IAC-99. Infestations of berry borer and leaf miner were
evaluated in fruits and leaves, respectively. The pests were monitored at 67 georeferenced points in an area of 6.6 ha in
2005, 2006 and 2007. Variograms estimated by the method of moments (MoM) and residual maximum likelihood REML were compared.
The latter were generally better in terms of the kriging error coefficients. Spherical variograms estimated by REML for berry
borer infestation in fruits had ranges of spatial dependence of 34.62–118.4 m and for the leaf miner they were 53.93–133.7 m.
For models fitted by weighted ordinary least squares (OLS) to the MoM experimental variogram, the ranges varied between 37.22
and 68.67 m for the berry borer and 100 and 155.4 m for leaf miner infestation. The variogram model parameters were used with
the data for ordinary kriging to map the spatial variation of coffee pests for different monitoring periods. If there was
no suitable variogram, inverse distance weighting was used to map the variation. The maps enabled visualization of the intensity
of infestation of the insect pests for the different periods evaluated. 相似文献
168.
The influence of Tribulus terrestris on the activities of testicular enzyme in Poecilia latipinna was assessed in lieu of reproductive manipulation. Different concentrations of (100, 150, 200, 250, and 300 mg) Tribulus terrestris extract and of a control were tested for testicular activity of enzymes in Poecilia latipinna for 2 months. The testis and liver were homogenized separately in 0.1 mol/l potassium phosphate buffer (0.1 mol/l, pH 7.2).
The crude homogenate was centrifuged, and supernatant obtained was used as an enzyme extract for determination of activities.
The activities of testicular functional enzyme ALP, ACP, SDH, LDH, and G6PDH levels were changed to different extent in treated
groups compared with that of the control. The total body weight and testis weight were increased with the Tribulus terrestris-treated fish (Poecilia latipinna). These results suggest that Tribulus terrestris induced the testicular enzyme activity that may aid in the male reproductive functions. It is discernible from the present
study that Tribulus terrestris has the inducing effect on reproductive system of Poecilia latipinna. 相似文献
169.
深受利用方式影响的农业土壤碳库在缓减大气二氧化碳浓度增加和温室效应加剧方面具有十分重要的作用.为了明确区域稻田土壤碳库蓄积量及其空间分布特征,以全国第二次土壤普查数据资料为基础,运用地理信息系统软件Arcview建立研究区以土种为单位的空间数据库,结合GIS空间分析功能,基于土壤类型法估算重庆市巴南区稻田土壤有机碳储量及其空间分布特征,结果表明:研究区稻田土壤有机碳总储量约为6.48×106t,平均土壤有机碳密度为8.31 kg/m2,略高于全国平均水平.重庆市巴南区稻田0~20 cm土壤有机碳密度介于1.73~3.70 kg/m2之间,剖面土壤有机碳密度介于5.13~14.07 kg/m2之间.0~20 cm和100 cm土壤有机碳储量分别为1.18×106 t和4.39x106t,0~20 cm土壤有机碳储量为0~100 cm碳储量的27.50%,说明碳储量主要富集在表层土壤.土壤有机碳密度呈带状分布,且具有高度的不均匀性,同类土壤具有相似的有机碳蓄积量. 相似文献
170.
Holland WG Thanh NG Do TT Sangmaneedet S Goddeeris B Vercruysse J 《Tropical animal health and production》2005,37(6):457-467
This study is concerned with the evaluation of established diagnostic tests for diagnosis of Trypanosoma evansi in pigs. The immune trypanolysis test (TL), card agglutination test (CATT), latex agglutination test (LATEX), enzyme-linked
immunosorbent assay (ELISA), microhaematocrit centrifugation technique (MHCT) and mouse inoculation (MI) tests were initially
evaluated in experimentally infected fattening pigs. All infected pigs were confirmed parasitologically positive with both
MHCT and MI. Results of the serological assays indicated that the TL could be a reference test for the presence of RoTat 1.2
antibodies in pigs. The results of the CATT and LATEX were inconsistent with the TL while the ELISA results correlated with
the TL results. The four serological assays were subsequently used in two field surveys in Vietnam and Thailand. Results of
the two agglutination assays (CATT and LATEX) were not consistent and did not correlate with TL results. The ELISA at percentage
positivity of 22 appeared to have good ability to discriminate between seropositive and seronegative animals. Of the 437 samples
collected at smallholder pig premises in northern Vietnam, no positive pigs were detected with the TL test. In Thailand, 77
samples were collected from five farrowing farms with a history of surra. Two parasitologically positive sows were found and
on each farm seropositive sows were detected. 相似文献