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51.
[目的]研究曝气生物滤池对污水厂出水的深度处理效果。[方法]采用上流式曝气生物滤池对污水厂出水进行深度处理,研究气水比、水力负荷对处理效果的影响,分析滤池中沿程微生物活性与污染物降解规律。[结果]在气水比4∶1,水力负荷为0.35m3/(m2·h)时,COD的去除效率为54%,色度的去除率为78%,NH3-N去除率为91%,满足GB/T 18920-2002城市杂用水水质标准。试验条件下,60 cm滤料层以下为COD降解主要区域,60~90 cm为NH3-N降解主要区域。生物量沿滤池高度范围逐渐降低,并趋于稳定,微生物活性呈现先升高后降低再升高的趋势。[结论]该研究可为污水处理厂污水处理工艺提标升级提供基础数据和理论支撑。 相似文献
52.
有机肥施用量对残塬沟壑区苹果园土壤优先流特征的影响 总被引:2,自引:1,他引:1
为研究有机肥施用量对残塬沟壑区苹果园土壤优先流特征的影响,以残塬沟壑区苹果园为研究对象,采用室外染色示踪法结合形态学和统计学方法,对永寿县苹果园土壤垂直染色剖面进行定量分析,使用均方差决策法综合各优先流特征指标对0 kg/hm2(CK)、6 000 kg/hm2(T1)、9 000 kg/hm2(T2)、12 000 kg/hm2(T3)四种不同有机肥施用量苹果园土壤优先流特征进行研究。结果表明:①不同有机肥施用量样地土壤染色面积比随土壤深度的变化状况均与Logistic曲线拟合程度较好,决定系数R2均大于0.986。②选用的优先流特征指标中基质流入渗深度、优先流分数、变异系数和分形维数与均方差决策法计算出的优先流发育程度结果一致,优先流发展程度表现为T3>T2>T1>CK。但平均最大入渗深度、优先流区染色面积比和长度指数在评价优先流程度中结果有些偏差,表现为T3>T2>CK>T1。③利用均方差决策法得到的优先流指数由大到小为:T3(0.75... 相似文献
53.
采用毛竹为原料制造竹基纤维复合材料,研究碱性染料的不同染色工艺对纤维化竹单板的上染效果及对毛竹竹基纤维复合材料的静曲强度、弹性模量、吸水厚度膨胀率与水平剪切强度的影响。结果表明:漂白后75℃醇溶剂媒介染色与90℃水染染色上染最终效果优于20℃水染。采用20℃水染染色制得的材料各项力学性能最优,各工艺制备的竹基纤维复合材料的物理与力学性能达到了重组竹地板国家标准的主要性能要求。 相似文献
54.
Sung?Dong?KimEmail author Min?Jung?Kim Byung?Sun?Lee Kwon?Sun?Lee 《Fibers and Polymers》2004,5(1):39-43
Effects of chemical structure of disperse dyes applied to conventional and microdenier polyesters on the dyeing property and
washfastness were studied. It was found that washfastness of dyed polyester fabric is closely related to the degree of thermomigration
of disperse dye during heatsetting. The bulky disperse dye, which was synthesized by substituting two acetoxy groups of C.I.
Disperse Red 82 with two benzoxy groups, showed almost the same amount of absorbed dye by the microdenier polyester as C.I.
Disperse Red 82, but the degree of thermomigration was low and subsequent washfastness was excellent. The high grade of washfastness
of the bulky disperse dye might be caused by the increased dye-fiber interaction and the reduced mobility. 相似文献
55.
In this paper, a comparison between a mathematical and an experimental method for the evaluation of some process components
of polyester microfibre dyeing is presented. In the experimental part, a dyeing procedure was chosen, K/S values of the dyed
samples were measured and the coefficients of the mathematical formula presented in the mathematical part were obtained. K/S
values of different dyeing procedures were also measured. In the mathematical part, predicted K/S values were calculated by
a novel formula. The results of the two methods were then compared. According to the results obtained, the mathematical formula
presented in this study can be used for calculating the predicted K/S values at lower dye concentrations. 相似文献
56.
Nine disperse dyes have been synthesized by diazotization of 2-amino-4-(p-nitrophenyl)-5-nitrothiazole and coupled to substituted
N-alkylanilines. Spectral properties in the IR and visible range of the dyes obtained were investigated. The dyeing performance
of these dyes was assessed on nylon and polyester fibers. These dyes were found to give reddish brown to bluish violet shades
on dyeing with very good depth, brightness and levelness on nylon and polyester fibers. The dyed fibers showed fairly good
light fastness, very good to excellent fastness to wash, rubbing, perspiration and excellent fastness to sublimation. The
dyebath exhaustion and fixation on the fiber were found to be very good. 相似文献
57.
58.
Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods
were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle
strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods
and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8 % weight loss and
2.4 % strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium
to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8 % weight loss and 18 % strength loss.
BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellow-ness was reduced to 64.5 from 83.1
and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the pre-metallised
dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color
clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity
of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results. 相似文献
59.
Kwon Sun Lee Beom Soo Lee Young Hwan Park Yoon Chul Park Yong Min Kim Sung Hoon Jeong Sung Dong Kim 《Fibers and Polymers》2005,6(1):35-41
Research and development of nano fiber products is very active over the world. Physical characteristics and dyeing properties
of nylon 66 nano fiber were investigated in this study. X-ray diffraction, DSC, analysis of amino end group, and water absorption
were performed to get information concerning physical properties of nano fiber. Nylon 66 nano fiber was dyed with high molecular
mass acid dyes. Effects of dyeing temperature, pH of dyeing solution, and concentration of acid dyes on dyeing properties
such as rate of dyeing and the extent of exhaustion, were examined and compared to those of regular fiber. It was found that
nano fiber adsorbed acid dyes at lower temperature, got rapidly dyed, and its extents of exhaustion at specific dyeing temperature
were higher than regular fiber. It was also observed that nano fiber could adsorb a large amount of acid dye without a significant
loss in the extent of exhaustion. Washing fastness of the dyed nano fiber was lower by 1/2∼1 grade, light fastness by 1 grade
than the dyed regular fiber. 相似文献
60.