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991.
Yang Y.Ren H.Zhai H. 《林产化学与工业》2018,(4):9-12
In order to solve the quantitative problem of the solubility of lignocellulosic biomass in the solvent system, wheat straw was studied as raw material for a ball milling time on its dissolution behavior in the LiCl/DMSO system. The dissolution performance was evaluated by visual method, optical microscopy and turbidity method respectively. By comparison of visual colorimetry method and the optical microscopy method at the condition of wheat straw dissolved in 8% LiCl/DMSO, it was found that the turbidimetric method is accurate, simple and quantitative. The turbidimetric method can be used to evaluate the dissolution behavior of lignocellulosic biomass during pretreatment and refining. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved. 相似文献
992.
鱼菜共生池塘养鱼技术是一种生态养鱼技术,它是依据鱼类和植物的生长环境、营养生理和理化知识等特点,结合水产养殖与蔬菜养殖这两种不同的农业养殖技艺,进行科学的生态规划,实现和谐共生。通过对重庆市九龙坡鱼菜共生项目的研究,说明这种养殖技术存在巨大的经济效益,值得推广。 相似文献
993.
Khadija Semhi René Boutin Nallusamy Sivakumar Walid Al Busaidi Abdallah Al Hamdi Khamis Al Dhafri Ahmed Al Busaidi 《Water, air, and soil pollution》2018,229(9):294
A radish and a grass species were grown in identical substrates either unpolluted or polluted by tungsten (W) at 1, 5, and 10 μg/g levels of watering solutions during 1 month under controlled laboratory conditions. Initially, at 4.1 μg/g, the W content in grass leaves reached 16 μg/g at the highest rate of W supply to the substrate. For radish, the content of W reached 22 and 29 μg/g in the leaves and roots, respectively. The overall W pollution increased significantly the mobility of major elements from substrate to grass leaves, especially at the 5 μg/g pollution level, whereas the W impact on radish leaves resulted in an increase of most contents, only Mn remaining unaffected. The roots from polluted radishes were enriched in Si by 21% and Al by 42% at low pollution, and in Si by 15% at high supply, whereas the uptake of the other elements remained unchanged. It looks like the W pollution at the levels chosen does not impact the transfer of the major and trace elements from roots to leaves of Raphanus sativus. Alternatively, metallic trace elements (Ba, Ni, Cr, Zn, W, Co) of the Raphanus sativus and Chloris gayana leaves outline similar content changes depending on the amount of W pollution. The total rare-earth element contents of the leaves of Raphanus sativus grown in the polluted substrates are lower than those of the leaves from unpolluted substrate. Their normalization in the leaves and roots of Raphanus sativus from the polluted substrates to those of the radish from non-polluted substrate provides flat patterns for both with a positive Eu anomaly for leaves, as for those of the grass and a negative Gd anomaly for roots. Also, addition of soluble W to the substrates induced an increase in the bacterial activity of the soil. 相似文献
994.
Chuang Yu Zezhong Ren Junfeng Liu Xiaoqing Cai Jianjun Ma Xiaoniu Yu 《Water, air, and soil pollution》2018,229(10):323
For the understanding of contaminant transport and transformation through landfill liner soils, most models are proposed with one-dimensional solutions. However, for large-scale contamination analysis, the one-dimensional analytical equations are not valid owing to the restriction of contaminants moving in horizontal direction. Thus, semi-analytical solutions for two-dimensional transport and transformation of contaminants through soil media with the consideration of large-strain deformation have been developed. To achieve this, Gibson’s large-strain consolidation theory is applied to capture the deformation of soil media under loading, with self-weight effects being taken into account. Transport and transformation of dissolved or sorbed contaminates in fully saturated finite soil medias are captured by extending a well-developed advection-dispersion model in two-dimensional space. The proposed analytical solutions are validated through simulating the process of coupled transport-transformation process of contaminants and consolidation of a finite soil layer. Profiles of contaminant concentration for different cases have been compared and discussed. The resulting simulation shows that large-strain deformation would restrict the transport and transformation of contaminants significantly, in both horizontal and vertical directions. Parameter studies also indicate that, with the increasing depth of soil layer, the breakthrough time for contaminants increases dramatically; diffusion coefficients affect the two-dimensional distributions of contaminant concentration and fate of contaminant in layered soil significantly. The numerical findings of this study can provide proper suggestions for the design of landfill liners. 相似文献
995.
Pengfei Wang Xiaopeng Mu Junjie Du Yu Gary Gao Donghai Bai Luting Jia Jiancheng Zhang Haiyan Ren Xiaofang Xue 《林业研究》2018,29(1):55-63
The Chinese dwarf cherry (Cerasus humilis (Bge.) Sok.) is a small shrub with edible fruits. It is native to northern and western China. This species was included as a medicinal plant in the “Chinese Pharmacopeia” and has emerged as an economically important crop for fresh fruit consumption, processing into juice and wine and nutraceutical products as well. To gain a better understanding of flavonoid biosynthesis and help develop value added products and better cultivars with greater health benefits, we analyzed total flavonoid content (TFC), composition, and radical scavenging activities in fruit extracts of 16 Chinese dwarf cherry genotypes. Fruit peel TFC ranged from 33.5 to 72.8 mg/g RE·FW (RE: rutin equivalent, FW: fresh weight) while fruit flesh TFC ranged from 4.3 to 16.9 mg/g RE·FW. An HPLC analysis revealed that fruit extracts contained 14 flavonoids with considerable variation in their profiles across genotypes. The most abundant flavonoids in most genotypes were proanthocyanidin B1 (PA-B1), proanthocyanidin B2 (PA-B2), phloretin 2′-O-glucoside (PG), and phloretin 2′,4′-O-diglucoside (PDG). Principal component analysis showed that PG, PA-B1, and PA-B2 had large, positive factor loading values in the first principal component for each genotype. Increased scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was apparent in genotypes ‘Nongda 4’, ‘Nongda 3’, ‘Nongda 6’, ‘Wenfenli’, and ’10-32’, suggesting promising applications in the production of nutraceutical products. In summary, our results will aid in breeding, fruit processing, and developing medicinal uses of the Chinese dwarf cherry. 相似文献
996.
997.
本文对屠宰环节现行检疫验讫印章在管理和使用方面存在的管理机制不完善、印章样式不统一,以及印章字迹不清、印油使用等印章使用不规范问题进行了探讨,并针对问题提出相应建议,供在《动物检疫管理办法》修订中参考。 相似文献
998.
999.
[目的]探究钾肥在抗大白菜软腐病中的作用。[方法]以德高秋丰王和北京新三号为试验材料,通过大田试验,研究3个施钾水平下(0、200、400 kg/hm~2K_2O)德高秋丰王和北京新三号大白菜产量、软腐病发病率及保护酶活性的变化。[结果]施钾量为200 kg/hm~2时显著提高德高秋丰王的产量,而北京新三号产量在施钾量达到400 kg/hm2时显著提高;随施钾量的提高,两品种大白菜软腐病病情指数都呈现降低的趋势,施钾量在400 kg/hm~2时,病情指数最低;两品种的PPO和POD的活性都随施钾量的提高而增强。[结论]施钾对大白菜产量的效应因品种不同而异,增施钾肥可以通过提高保护酶的活性降低大白菜软腐病病情指数。 相似文献
1000.
Genetic mapping using 1.4M SNP array refined loci for fatty acid composition traits in Chinese Erhualian and Bamaxiang pigs
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J. Zhang Y. Zhang H. Gong L. Cui T. Huang H. Ai J. Ren L. Huang B. Yang 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(6):472-483
Chinese indigenous pigs display marked genetic and phenotypic differences compared with western commercial pigs. In this study, we tested the association between 660K SNPs and longissimus muscle fatty acid composition traits in Chinese Erhualian (n = 331) and Bamaxiang (n = 315) pigs based on a customized 1.4 million SNP array. We identified a total of 64 significant associations for 20 fatty acid composition traits at the p‐value threshold of 1 × 10?6 among which 42 associations in low linkage disequilibrium (r2 < .2) with previously reported loci were considered novel. We substantially improved the strength and precision of the associations at four previously detected loci near FADS2, ELOVL7, ELOVL6 and FASN genes, facilitating follow‐up candidate gene studies. Moreover, we also identified loci near ABCD2, ACSBG1, ELOVL5, HPGDS, DAGT2, ACAD10 and ACSL1 genes with function relevant to metabolism of fatty acids. In this study, valuable genetic variants and candidate genes associated with fatty acid composition traits were identified in Erhualian and Bamaxiang pigs. Some identified loci could be used to improve pork nutrition in pig breeding practice. Using the SNP array with higher marker density and less ascertainment bias improved QTL detection power and precision in Chinese indigenous pigs. 相似文献