oalib

OALib Journal期刊

ISSN: 2333-9721

费用：99美元

投稿

时间不限

( 2673 )

( 2672 )

( 2454 )

( 2024 )

自定义范围…

匹配条件： “ Xiangyang Huang” ，找到相关结果约41774条。
列表显示的所有文章，均可免费获取
第1页/共41774条
每页显示 条
A Review of Main Factors Leading to Air Pressure Fluctuations in Branch Drainage Pipes inside Buildings  [PDF]
Rodger Millar Munthali, Xiangyang Huang
Journal of Building Construction and Planning Research (JBCPR) , 2021, DOI: 10.4236/jbcpr.2021.91006
Abstract: This paper is to discuss the main factors leading to the air pressure fluctuations in appliance branch pipes and measures to control them. It has been established that the main factors characteristics of a good sanitary pipework system are that it must prevent the transmission of foul air into the building, minimize blockages, provide efficient conveyance of discharge from sanitary appliances and minimize the risk of flooding to any part of a building. However, due to the nature and properties of sanitary appliance discharge, the flow being a three-phase flow which is simplified to two-phase for design computations and discharge being probabilistic, air variations in the horizontal appliance pipe result in phenomenon in which the sanitary network fails to perform as designed and installed to prevent or minimize aforementioned circumstances. It has been established that the main factors to be discussed leading to air pressure fluctuations in the appliance branch pipe are water traps, bend structures, pipe diameter, pipe slope and length, angle and connection mode and ventilation conditions. These factors’ associated control measures have also been presented. However, factors pertaining to concentration of appliance discharge have not been discussed. The result of this discussion will enable designers and installers of sanitary pipework to incorporate measures to control air pressure fluctuations in appliance branch pipes inside buildings.
Metal-insulator transition in VO$_{2}$: a Peierls-Mott-Hubbard mechanism
Xiangyang Huang,Weidong Yang,Ulrich Eckern
Physics , 1998,
Abstract: The electronic structure of VO$_2$ is studied in the frameworks of local density approximation (LDA) and LDA+$U$ to give a quantitative description of the metal-insulator (MI) transition in this system. It is found that, both structural distortion and the local Coulomb interaction, play important roles in the transition. An optical gap, comparable to the experimental value has been obtained in the monoclinic structure by using the LDA+$U$ method. Based on our results, we believe that both, the Peierls and the Mott-Hubbard mechanism, are essential for a description of the MI transition in this system.
Virtual Screening of Inhibitors for Chitosanases EAG1  [PDF]
Xiangyang Xu, Zaiwei Song, Yunchao Yin, Faguo Zhong, Junying Song, Jiachao Huang, Wangli Ye, Peng Wang
Advances in Enzyme Research (AER) , 2020, DOI: 10.4236/aer.2020.84005
Abstract: Chitosanases EAG1 is a classical glycoside hydrolase from Bacillus ehimensis. The previous researches showed that this Chitosanases can not only hydrolyze the b1,4-glycosidic bonds of chitosan to COS in different sizes but also keep a high catalytic activity in organic, which was useful for producing chitooligosaccharides and GlcN for use in the food and pharmacological industries. While it is instable in the liquid state. This shortcoming seriously restricts its industrial application. Here we used the modeled structure of EAG1 and the molecular modeling software package to screen the free chemical database ZINC. Moreover, the strategies including “initial filter” and consensus scoring were applied to accelerate the process and improve the success rate of virtual screening. Finally, five compounds were screened and they were purchased or synthetized to test their binding affinity against EAG1. The test results showed that one of them could inhibit the enzyme with an apparent Ki of 1.5 μM. The result may take the foundation for further inhibitor screening and design against EAG1 and the screened compound may also help to improve the liquid stability of EAG1 and expand its industrial application.
Solid-State Fermentation Production of Chitosanase by Streptomyces with Waste Mycelia of Aspergillus niger  [PDF]
Xiangyang Xu, Zaiwei Song, Yunchao Yin, Faguo Zhong, Junying Song, Jiachao Huang, Wangli Ye, Peng Wang
Advances in Enzyme Research (AER) , 2021, DOI: 10.4236/aer.2021.91002
Abstract: Solid-state fermentation was carried out using mycelium powder of Aspergillus niger as substrate for the production of chitosanase of Streptomyces. Results of the experiments indicated that the optimal medium consisted of wheat bran and mycelium powder of Aspergillus niger with initial moisture content of 60% - 70%. The enzyme activity reached 41.33 U per gram dry medium after cultured for 5 days at 28°C - 30°C and an initial pH 6.5. Chitosanase was detected on the second day of incubation and had maximal activity at 5 days and decreased gradually within a 1 month period. Solid-state fermentation is maybe an economic alternative in the production.
Analyses of the oligopeptide transporter gene family in poplar and grape
Jun Cao, Jinling Huang, Yongping Yang, Xiangyang Hu
BMC Genomics , 2011, DOI: 10.1186/1471-2164-12-465
Abstract: In the present study, a comprehensive analysis of the OPT gene family in Populus (P. trichocarpa) and Vitis (V. vinifera) was performed. A total of 20 and 18 full-length OPT genes have been identified in Populus and Vitis, respectively. Phylogenetic analyses indicate that these OPT genes consist of two classes that can be further subdivided into 11 groups. Gene structures are considerably conserved among the groups. The distribution of OPT genes was found to be non-random across chromosomes. A high proportion of the genes are preferentially clustered, indicating that tandem duplications may have contributed significantly to the expansion of the OPT gene family. Expression patterns based on our analyses of microarray data suggest that many OPT genes may be important in stress response and functional development of plants. Further analyses of functional divergence and adaptive evolution show that, while purifying selection may have been the main force driving the evolution of the OPTs, some of critical sites responsible for the functional divergence may have been under positive selection.Overall, the data obtained from our investigation contribute to a better understanding of the complexity of the Populus and Vitis OPT gene family and of the function and evolution of the OPT gene family in higher plants.Substrate transport is vital for all living organisms, and many transporters play important roles in this process. More than 600 transporter families are currently documented in the Transporter Classification Database (TCDB) [1,2]. These protein families are further classed into seven subclasses (channels/pores, electrochemical potential-driver transporters, primary active transporters, group translocators, transport electron carriers, accessory factors involved in transport, and incompletely characterized transport systems). In general, they have specific localizations within the cell and are specialized to carry different compounds, including nitrate, phosphate, sucr
No miRNA were found in Plasmodium and the ones identified in erythrocytes could not be correlated with infection
Xiangyang Xue, Qingfeng Zhang, Yufu Huang, Le Feng, Weiqing Pan
Malaria Journal , 2008, DOI: 10.1186/1475-2875-7-47
Abstract: Of 132 small RNA sequences, no Plasmodium-specific miRNAs have been found. However, a human miRNA, miR-451, was highly expressed, comprising approximately one third of the total identified miRNAs. Further analysis of miR-451 expression and malaria infection showed no association between the accumulation of miR-451 in Plasmodium falciparum-iRBCs, the life cycle stage of P. falciparum in the erythrocyte, or of P. berghei in mice. Moreover, treatment with an antisense oligonucleotide to miR-451 had no significant effect on the growth of the erythrocytic-stage P. falciparum.Short RNAs from a mixed-stage of P. falciparum-iRBC were separated in a denaturing polyacrylamide gel and cloned into T vectors to create a cDNA library. Individual clones were then sequenced and further analysed by bioinformatics prediction to discover probable miRNAs in P. falciparum-iRBC. The association between miR-451 expression and the parasite were analysed by Northern blotting and antisense oligonucleotide (ASO) of miR-451.These results contribute to eliminate the probability of miRNAs in P. falciparum. The absence of miRNA in P. falciparum could be correlated with absence of argonaute/dicer genes. In addition, the miR-451 accumulation in Plasmodium-infected RBCs is independent of parasite infection. Its accumulation might be only the residual of erythroid differentiation or a component to maintain the normal function of mature RBCs.MicroRNAs (miRNAs), a newly discovered class of endogenous ~21 nucleotide regulatory non-coding small RNAs, post-transcriptionally regulated gene expression in eukaryotes by targeted RNA degradation and translational arrest [1]. Similarly to short interfering RNAs (siRNAs), miRNAs are produced in the cytoplasm from a precursor, which contains an imperfectly matched inverted repeat forming a partial double-stranded region, by the ribonuclease, dicer. One strand of the resulting miRNA duplex intermediate is then recruited by the argonaute nuclease, an enzyme involve
GCC box inArabidopsis PDF1.2 promoter is an essential and sufficient cis-acting element in response to MeJA treatment
Haiwen Zhang,Bingyan Xie,Xiangyang Lu,Yuhong Yang,Rongfeng Huang
Chinese Science Bulletin , 2004, DOI: 10.1007/BF03183717
Abstract: The expression ofArabidopsis PDF1.2 gene is regulated by jasmonic acid (JA) and ethylene (ET). It also has been well documented that GCC box is an element responsive to ET, however, the responsive mechanism of JA in such plant defense gene expression is unclear. In this paper, the authors define the essential cis-acting element inPDF1.2 promoter responsive to methyl jasmonate (MeJA) through fragment deletions and site-directed mutageneses combiningAgrobacterium-mediated transient reporter gene expression in tobacco leaves. Firstly, the MeJA inducible expression ofPDF1.2 was confirmed by using the upstream 1.86 kb fragment ofPDF1.2 gene. Secondly, the upstream 300– 243 bp fragment of the promoter was evidenced to respond to MeJA. To further characterize this promoter region, three point mutations were introduced into the 300– 243 bp fragment of the promoter. This result showed that the mutation of GCC box abolished MeJA induction, whereas the mutations of the G box-like and the imperfect palindrome sequence did not significantly decrease MeJA inducible effect, indicating that GCC box inPDF1.2 is essential for MeJA induction. The sufficient responsiveness to MeJA of this GCC box was further investigated by 4×GCC fused upstream to the CaMV 35S minimal promoter. This result suggested that the fused promoter was able to activate reporter gene expression in response to MeJA. Thus these results indicate that the GCC box inPDF1.2 is an essential and sufficient element to confer MeJA induction.
Effect of tail-water of lake water source heat pump system on lake eutrophication process
湖水源热泵系统尾水排放对湖泊富营养化进程的影响研究
Huang Xiangyang,Zhou Jian,
黄向阳,周健
环境工程学报 , 2010,
Abstract: 以重庆市开县人民医院湖水源热泵工程为例，通过对该工程运行期间尾水受纳湖泊水域水温、氮、磷和浮游植物的长期监测，研究了湖水源热泵系统尾水对湖泊富营养化进程的影响。结果表明，夏季系统的长期运行导致了排放口附近水域水温的升高；当系统温排水水温在30℃以下时，温排水造成的温升使得排放口附近氮、磷含量升高，蓝、绿藻数量大幅增加，加速了湖泊的富营养化进程；当温排水水温达到33℃以上时，过高的温度会抑制藻类的生长。冷排水使湖泊排放口近水域浮游植物总量降低，且硅藻占总藻的比例增大，冷排水同时抑制了蓝藻和其他一些藻类的生长
Modeling of Task Establishment and Allocation for Collaborative Virtual Maintenance Training of Complex Equipment
Xiangyang Li,Zhili Zhang,Qinhe Gao,Xianxiang Huang
Research Journal of Applied Sciences, Engineering and Technology , 2012,
Abstract: In this study, we propose the maintenance task establishment method based on fault simulation models. Maintenance task allocation model based on Multi-Agent System and High Level Architecture is presented to manage and coordinate the dynamic task allocating process of multi operators and it can make the intelligent decision for their collaborative maintenance operation at each step. Object information template is designed with the Extensible Markup Language to perform interactive communication of the heterogeneous data and information in the different models of collaborative virtual maintenance training system, which ensures the efficient share of the data resource for the collaborative maintenance operations. Finally, the simulation research on a mechanical-electronic-hydraulic integrated subsystem in complex equipment is done and the simulation execution and results show the effectiveness of the proposed methods.
First-principles study of the structural energetics of PdTi and PtTi
Xiangyang Huang,Karin M. Rabe,Graeme J. Ackland
Physics , 2002, DOI: 10.1103/PhysRevB.67.024101
Abstract: The structural energetics of PdTi and PtTi have been studied using first-principles density-functional theory with pseudopotentials and a plane-wave basis. We predict that in both materials, the experimentally reported orthorhombic $B19$ phase will undergo a low-temperature phase transition to a monoclinic $B19'$ ground state. Within a soft-mode framework, we relate the $B19$ structure to the cubic $B2$ structure, observed at high temperature, and the $B19'$ structure to $B19$ via phonon modes strongly coupled to strain. In contrast to NiTi, the $B19$ structure is extremely close to hcp. We draw on the analogy to the bcc-hcp transition to suggest likely transition mechanisms in the present case.
第1页/共41774条
每页显示 条


Home
Copyright © 2008-2020 Open Access Library. All rights reserved.