Subjects: Biology >> Botany >> Applied botany submitted time 2024-04-17 Cooperative journals: 《广西植物》
Abstract： Expansin (EXP) plays an important role in plant response to environmental stress by regulating cell wall relaxation. To explore the role of EXP genes in soybean response to abiotic stress, two soybean EXP genes (GmEXPB5 and GmEXPB7) and their protein sequences were analyzed by bioinformatics, and their expression levels were detected by real-time fluorescent quantitative PCR (qRT-PCR). The results were as follows: (1) The GmEXPB5 and GmEXPB7 were located on chromosomes 10 and 12 of soybean, and encoded proteins containing 272 and 267 amino acids, respectively. The molecular weight of GmEXPB5 protein was 29.07 kD and the theoretical isoelectric point was 7.51. The molecular weight of GmEXPB7 protein was 29.09 kD and the theoretical isoelectric point was 8.66. Both GmEXPB5 and GmEXPB7 were stable hydrophilic proteins localized in the cell wall. Both GmEXPB5 and GmEXPB7 proteins contained a signal peptide sequence and a conserved DPBB_1 domain. (2) GmEXPB5 was closely related to CaEXPB15 of chickpea, and GmEXPB7 was closely related to EXPB3 of chickpea, red bean and cowpea. (3) GmEXPB5 and GmEXPB7 were expressed in soybean roots, stems and leaves, and their expression levels in roots and leaves were significantly higher than those in stems. (4) GmEXPB5 and GmEXPB7 could respond to salt, drought and cold stresses in soybean seedlings. (5) The promoter region of GmEXPB5 contained two types of stress-related cis-elements (ABRE and ARE). The promoter region of GmEXPB7 contained five types of stress-related cis-elements (ABRE、ARE、CGTCA-motif、TC-rich repeats and MBS). These results indicated that GmEXPB5 and GmEXPB7 could participate in the response of soybean to abiotic stress.
Subjects: Geosciences >> Geography submitted time 2023-04-07 Cooperative journals: 《干旱区地理》
Abstract： Ecosystem services are closely linked to sustainable human development. Studying the supply and demand characteristics of regional ecosystem services and comprehending their spatial matching status are essential prerequisites for achieving the efficient allocation of ecological resources and promoting regional ecological security. The water production, carbon sequestration, and food services of the Shule River Basin in the Gansu Province of China were all examined on the basis of multisource data and with the assistance of the InVEST model as well as the ArcGIS and GeoDA software. The following are the results of this study: (1) There are discrepancies between different regions and ecosystem services; except for water production services, the supply of other ecosystem services in the Shule River Basin is more than the demand. (2) The supply-demand ratio of comprehensive services in the Shule River Basin is 0.063, and the supply-demand ratios of different ecosystem services are carbon sequestration services (0.1854) >food services (0.0078) >water production services ( −0.0043). (3) Water production and carbon sequestration service spaces are mainly based on low-high-type and high-low-type spatial dislocation, respectively, whereas food service spaces are primarily based on low-low-type spatial matching, among which the spatial mismatch of water production services is the most severe.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： Single crystal (SC) superalloy is a kind of complex structure and multi phase materials. With the increase of the degree of alloying and the content of refractory elements, or the more complicated structure and larger size of the casting made of SC superalloy, it is essential important to suppress the formation of solidification defects to improve the quality and performance of the blades. The microstructure and solidification defects of single crystal alloy are not only related to the composition of the alloy, but also depend on its solidification characteristics and technological conditions. The paper first summarizes the research progress of the solidification characteristics for advanced SC superalloys, focusing on analysis of the effects of solidification characteristics and processing parameters on the formation and its mechanics for two typical directional solidification defects, crystallographic orientation deviation and stray grains. Then some methods and approaches to suppress such defect formation for complex single crystal blade have been reviewed.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2019-01-28 Cooperative journals: 《计算机应用研究》
Abstract： Aiming at the texture synthesis in new computer graphics technical conditions, this paper proposes a texture interpolation method to synthesize different resolution textures adaptively from a single real world texture. The synthesized texture’s DPI is same as the original texture example. Firstly, the proposed method use a high-dimensional interpolation algorithm to generate an intermediate guidance texture with target resolution by split the source texture. Secondly, particular random patches are selected to fill the gaps in the intermediate texture according to the self-similarity in the source texture. Finally, these patches are seamlessly embedded in the previous intermediate texture by the Poisson image-editing algorithm. Experimental results show that the proposed method can handle both stationary and non-stationary texture synthesis, and the synthetic results are more consistent in the visual properties of the source texture. In addition, the implement logic of the proposed method is enough simple to be programing and executing on a common mobile platforms.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2019-01-03 Cooperative journals: 《计算机应用研究》
Abstract： In order to improve the accuracy of radar target recognition, this paper proposes a high resolution range profile (HRRP) recognition method based on deep belief network (DBN) . Firstly, the method uses a restricted Boltzmann machine (RBM) to perform layer-by-layer unsupervised training on HRRP data. The network parameters are updated according to the contrast divergence (CD) algorithm, and the DBN depth is designed by the reconstruction error method. Then, the DBN model parameters are supervised and fine-tuned through a back propagation (BP) mechanism. Finally, based on the model, the classification and recognition of HRRP is realized. The experimental results show that compared with the traditional neural network, the recognition accuracy and noise robustness of the deep belief network based on this paper are significantly improved, and the recognition accuracy can be improved by 8.5%.
Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究围产期母猪饲粮中添加壳寡糖（COS）对母猪、仔猪免疫功能和母猪肠道微生物的影响。选用体重、背膘厚度、胎次和预产期接近的40头健康大约克妊娠母猪，随机分为2个组，每组20个重复，每个重复1头母猪。对照组饲喂基础饲粮，试验组饲喂在基础饲粮中添加30 mg/kg COS的试验饲粮。试验期为母猪妊娠第90天至分娩后第7天。结果显示：1）围产期母猪饲粮中添加COS对母猪产程、总产仔数、产活仔数、仔猪初生窝重、仔猪平均初生重均无显著影响(P＞0.05)。2）围产期母猪饲粮中添加COS显著提高了母猪血清中免疫球蛋白G(IgG)、免疫球蛋白A(IgA)和白细胞介素-6（IL-6）含量（P＜0.05），对血清中免疫球蛋白M(IgM)、白细胞介素-2（IL-2）和肿瘤坏死因子-α（TNF-α）含量无显著影响(P＞0.05)。3）围产期母猪饲粮中添加COS显著提高了母猪初乳中IgG、IL-2和IL-6含量（P＜0.05），对IgA、IgM和TNF-α含量无显著影响(P＞0.05)。4）围产期母猪饲粮中添加COS显著提高了初生仔猪血清中IL-2和IL-6含量（P＜0.05），并显著降低血清中IgA的含量（P＜0.05）。5）围产期母猪饲粮中添加COS显著降低了母猪粪便中沙门氏菌的数量（P＜0.05），并有降低粪便中大肠杆菌数量的趋势（P＜0.10）。由此可见，围产期母猪饲粮中添加COS能够改善母猪肠道健康，一定程度上提高产活仔数，显著增强母猪及初生仔猪的免疫功能。
submitted time 2018-10-26 Cooperative journals: 《电气工程学报》
Abstract： For the voltage source PWM rectifiers which are increasingly widely used in micro-grids and many industrial fields, the main principles and double closed-loop control structure of the voltage source PWM rectifiers are briefly analyzed. According to the type of controlled quantity, the control system is divided into two categories including current and power, then the traditional, modern and intelligent control methods are comprehensively expounded based on the strategy. Finally the development trend of voltage source PWM rectifier control is expected in the paper.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-10-11 Cooperative journals: 《计算机应用研究》
Abstract： In solving the problem of multi-objective optimization operation of distributed power supply in micro-grid, aiming at the limitations of traditional NSGA-II algorithm in terms of approximation and computational efficiency, considering the difference of individual similarity in evolution process and the possibility of the algorithm falling into local optimum, this paper proposed an improved NSGA-II algorithm. The new algorithm introduced the information entropy mechanism to improve the operator, and approximated the crossover probability and mutation probability as the decreasing function model and the Cauchy distribution model respectively. The performance test proves that the new algorithm is effective. Taking distributed power supply access to IEEE 30-node power system as an example for simulation experiment, compared with the traditional NSGA-II multi-objective optimization algorithm, the result shows the superiority of the improved algorithm in improving the convergence speed and the optimization indices.
Subjects: Civil Engineering and Building Construction >> Civil Construction Engineering submitted time 2017-12-21 Cooperative journals: 《土木建筑工程信息技术》
Abstract： Panoramic photography is a special imaging technique which has been popular in recent years and has been widely applied. Panoramic photography can be used to generate 360-degree 3D scene images. Direct generation of panoramic camera，such as Ricoh or XiaoMi，is simple in operation but with impressive effect of the image. Just through one shot，the 360-degree 3 D images can be generated，with extensive applications of the scene.Introducing the panoramic camera panoramic model，the interactive roaming and the periodic aerial panorama records to the field of construction technology，will bring brand-new visual experience to the construction site management. Many engineering examples have shown that there is large space for the application of panoramic photography technology in the construction engineering.
Subjects: Civil Engineering and Building Construction >> Civil Construction Engineering submitted time 2017-12-05 Cooperative journals: 《土木建筑工程信息技术》
Abstract：3D打印模型源文件一般为特定格式的STL文件，现开发人员引入开源WebGL语言实现了HTMIS页面无需安装插件即可实现3D打印模型的在线浏览，无需任何浏览器插件支持，同时引入二维码编译脚本能实现手机端扫描二维码进行模型预览和源文件下载。BIM模型Web嵌入应用借助3dsmax开放式插件，将revit模型导入到 3dsmax, 3dsmax安装开放式模型上传插件实现一键生成HTMLS可直接打开的三维模型并附带渲染的纹理模型，浏览器终端支持旋转、放大、漫游及简易交互功能，可深入应用前景广阔。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本文旨在研究颈静脉灌注精氨酸对泌乳中期奶牛血清生化和免疫指标的影响。采用3×3复式拉丁方试验设计，选择6头体重、胎次、泌乳期、泌乳量和体况基本一致的荷斯坦奶牛为试验动物，随机分为3组（每组2头），分别为酪蛋白组（对照组）、精氨酸组[灌注37.66 g/(L·d)]、丙氨酸组[与精氨酸组等氮，灌注77.24 g/(L·d)]；每个试验期为22 d（7 d灌注+15 d间隔），在每个试验灌注期的最后1 d晨饲前采血，测定血清生化和免疫指标。结果表明：精氨酸组的奶牛血清中总蛋白、免疫球蛋白G(IgG)、肿瘤坏死因子α（TNF-α）浓度要显著高于其他2组（P0.05）。综上，灌注精氨酸能够通过提高血清总蛋白、IgG及IL-1、TNF-α的浓度，从而一定程度上增强泌乳奶牛机体的免疫力和胎儿的被动免疫力。
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：本文旨在研究颈静脉灌注精氨酸对泌乳中期奶牛泌乳性能和牛乳酪蛋白合成的影响。将6头体重、胎次、泌乳期、泌乳量和体况基本一致的荷斯坦奶牛随机分为3组（每组2头）：酪蛋白模式组（对照组）、精氨酸灌注组、丙氨酸等氮组（与精氨酸灌注组等氮），采用3×3复拉丁方试验设计，每期22 d（7 d灌注期+15 d间隔期），测定其泌乳性能、酪蛋白含量以及酪蛋白基因的表达情况。结果表明：1）灌注的第5天精氨酸灌注组的乳蛋白及乳中非脂固形物含量均显著高于酪蛋白模式组（P0.05）；κ-酪蛋白含量则以精氨酸灌注组为最高，显著高于其他2组（P<0.05）。3）精氨酸灌注组αs1-酪蛋白基因（CSN1S1）、αs2-酪蛋白基因（CSN1S2）的表达量显著高于其他2组（P<0.05）。综上，灌注精氨酸提高了乳蛋白中α-酪蛋白和κ-酪蛋白含量，以及CSN1S1、CSN1S2在奶牛乳腺组织的表达量，有利于牛乳中乳蛋白率和乳品质的提高。
Subjects: Materials Science >> Materials Science (General) submitted time 2017-04-10 Cooperative journals: 《材料研究学报》
Abstract：以 ZrCl4-BCl3-H2-Ar 作为化学气相沉积反应体系，在不同温度下化学气相沉积 ZrB2 涂层，用 X 射线衍射 和扫描电子显微镜(SEM)表征了涂层的微观形貌和晶粒择优生长。结果表明:在石墨基体表面 ZrB2 涂层的形 核模式为岛状生长，小岛不断生成和合并以及晶粒的生长使靠近石墨基体表面的涂层含有大量孔洞，并形成 细晶区。在1300~1600°C沉积的初期，ZrB2涂层中一次晶粒融合为二次晶粒，表现为方向的择优生长。 随着沉积的进行 ZrB2 涂层的形貌从二次晶粒生长为板块状晶粒，板块状晶粒进一步生长向金字塔形貌转变， 涂层内部生长为致密柱状晶，晶粒的择优取向从向转变;当金字塔形貌的晶粒棱边发生钝化时涂 层内部的晶粒向等轴晶转变，晶粒的择优取向由方向转变为方向。
Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《金属学报》
Abstract：通过对3种不同W(6%-8%, 质量分数, 下同)含量的第三代镍基单晶高温合金铸态, 热处理态和热暴露后的组织观察和成分分析, 研究了W对元素偏析, 热处理组织及热暴露过程中组织演化的影响. 结果表明: W含量的提高对合金元素的铸态偏析, 完全热处理后的γ′相形貌, 尺寸和体积分数无明显影响. 在950 ℃热暴露过程中, W含量的提高抑制了γ′相的粗化, 但加速了γ′相的连接变形. 3种合金在热暴露过程中析出的TCP相主要为μ相和σ相, 且TCP相析出量随W含量的增加缓慢增大. 此外, 3种合金在1000 ℃热暴露时TCP相析出量最大, 在950 ℃热暴露时次之, 在1050 ℃热暴露时析出量最小.
Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《金属学报》
Abstract：采用相场法研究了Fe-C-Mn三元合金在临界区等温过程中发生的奥氏体-铁素体相变. 基于Gibbs自由能平衡理论，相场模型考虑了替换性元素Mn在奥氏体/铁素体相界面内扩散所导致的自由能耗散，因此本模型可描述Fe-C-Mn三元合金中因Mn在相界面偏聚所导致的相变停滞和相变不完全现象. 利用相场模型进一步研究了不同Mn含量对奥氏体-铁素体相变微观组织转变和相变动力学的影响. 结果显示：随着Mn含量的增加，铁素体相的转变速率和最终体积分数降低，Mn在奥氏体/铁素体相界面内扩散所导致的溶质拖曳现象越明显，相变不完全的转变程度加剧.
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-15 Cooperative journals: 《金属学报》
Abstract：采用熔体超温处理技术对新型含Re和Ru的镍基单晶高温合金熔体进行了不同温度的超温处理，利用电子探针系统研究了定向凝固过程中合金元素的溶质分布状态及溶质分配系数随熔体超温处理温度变化的规律。结果表明，在平界面定向凝固条件下，熔体超温处理对Al、Ta、Ru、Re、W元素的分布和分配系数有明显的影响，而对Mo、Cr、Co元素无明显影响。随熔体超温处理温度的升高，Al、Ta元素在固液界面前沿液相一侧的分布呈现先增高后降低的趋势，而Re、W、Ru元素则呈现相反的规律。当熔体从1500℃过热到1700℃时，Al、Ta、Re、W元素的溶质分配系数趋近于1；进一步提高熔体温度至1800℃，各元素溶质分配系数逐渐偏离1，然而熔体超温处理温度对于Ru、Mo、Cr、Co的溶质分配系数的变化影响不大。熔体超温处理使合金熔体结构发生变化，并进而影响元素分布，是导致溶质分配系数发生变化的主要原因。
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-15 Cooperative journals: 《金属学报》
Abstract：运用相场法研究了Fe-C合金在临界区等温过程中发生的奥氏体-铁素体相变过程. 通过分析铁素体生长过程中C的扩散行为，发现奥氏体-铁素体相变表现为混合控制生长的特征，奥氏体/铁素体相界面处于非平衡状态. 进一步研究了不同等温温度（1010、1048和 1087K）下奥氏体-铁素体相变的微观组织和C浓度场的演化情况. 结果表明，随着等温温度的降低，铁素体形核率增加，铁素体相变平衡体积分数增加，但奥氏体内部C浓度分布的不均匀程度加剧，1010K等温时的微观组织呈现为不规则细小铁素体晶粒围绕分散分布的残余奥氏体的两相结构. 随着等温温度的降低，奥氏体-铁素体相变过程表现出由扩散控制生长模式向界面控制生长模式转化的趋势.
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