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991.
K.M. Feng Author Vitae G.S. Zhang G.Y. Zheng Z. Zhao T. Yuan Z.Q. Li G.Z. Sheng C.H. Pan 《Fusion Engineering and Design》2009,84(12):2109-2113
The basic definition and development strategy of the DEMO plant based on the Chinese fusion power plant (FPP) program are presented briefly. A conceptual design study of fusion HCSB-DEMO reactor with a fusion power of 2550 MW and a neutron wall loading of 2.3 MW/m2 is performed recently. Three sets parameters of core plasma for different DEMO design objectives are proposed. A helium-cooled blanket system with ceramic breeder (Li4SiO4), the structure material of low-activation ferritic steel (LAF/M) and Be neutron multiplier based on Chinese ITER HCSB-TBM design foundation are considered. The design parameters, preliminary analyses and the basic structure as well as development strategy of HCSB-DEMO reactor are introduced. 相似文献
992.
993.
在发动机叶片定向无余量精铸件的研制过程中,通过对叶片变形的分析,制定预防变形的措施,设计成型浇注系统、组合夹具等工装,加强控制手段,解决了超薄细长定向无余量叶片变形问题,提高了叶片的尺寸精度,研制出符合设计要求的无余量叶片. 相似文献
994.
The combined effect of previous dynamic high-pressure microfluidization treatment (40, 80, 120, and 160 MPa) and subsequent glycation with galacto-oligosaccharides (GOS) on the antigenicity of β-lactoglobulin (β-LG) was investigated. The antigenicity of β-LG-GOS decreased at relatively low pressure (≤120 MPa). Surface sulfhydryl group content of β-LG-GOS increased and surface hydrophobicity of β-LG-GOS decreased. Additionally, protein unfolding in β-LG-GOS samples was reflected by quenching of fluorescence intensity, the red-shift of fluorescence spectra, decreased UV absorption, and circular dichroism analysis, indicating tertiary and secondary structural changes of β-LG. The conformational changes may contribute to the alteration of antigenicity. 相似文献
995.
996.
Fabric woven from wool/polyester (PES) Murata vortex spun (MVS) blend yarn is a commercially viable proposition particularly on the basis of advantageous wear-resistant properties, compared with fabric made from traditional worsted ring-spun yarn. However, in some early industrial trials with fabric made from 45/55-blend wool/PES MVS yarn, significantly greater relaxation shrinkage was found relative to comparable worsted ring-spun fabric. It was noted at the time that the amount of relaxation shrinkage in MVS fabric could be reduced to a large extent by using steamed MVS yarn. In this study, the extent of variations in the dimensional and mechanical properties of fabric samples woven from a combination of steamed and unsteamed MVS yarn and equivalent worsted ring-spun yarn is examined. In general, greater hygral expansion and relaxation shrinkage were found in loom-state fabrics made from unsteamed MVS yarns, whereas the fabric made from steamed MVS and ring-spun yarns gave relatively low levels of relaxation shrinkage and hygral expansion. Permanent setting of fabrics, by pressure steaming, was found to be more effective than yarn pre-steaming in reducing relaxation shrinkage levels of fabrics made from unsteamed MVS yarn. After pressure steaming, all fabrics showed similar levels of relaxation shrinkage and hygral expansion. Permanent setting of the fabrics, by pressure steaming, resulted in similar levels of relaxation shrinkage and hygral expansion, irrespective of the yarn production method; relaxation shrinkage fell to around 1% and hygral expansion increased by about 1%, relative to the loom-state samples. MVS fabrics were relatively heavier and fuller and had a firmer handle than the worsted ring-spun fabrics, reflecting the greater fabric weight, thickness and shear rigidity measured on these fabrics. These attributes are associated with different structures of the worsted ring-spun and MVS yarns used to make the fabrics. 相似文献
997.
A recombinant plasmid, pRP-GFP, harboring the green fluorescent protein (GFP) gene from the broad-host-range mobilizable plasmid pRK415 of the RK2 family was constructed and transferred by conjugation from Escherichia coli S17-1 to Sorangium cellulosum So ce90. The results of Southern blot analysis showed that the plasmid replicated autonomously without being integrated into the chromosome of the bacterium. In pRP-GFP, gfp was driven by a So ce90 DNA fragment called EpoPro, which is an 890-bp DNA segment spanning from -890 to -1 relative to the start codon (GTG) of epoA, a gene that encodes EPOS A, which is presumed to be involved in the initiation of epothilone biosynthesis. The GFP in the transformed S. cellulosum So ce90 was detected by fluorescence microscopy, which suggests that the EpoPro fragment had the function of promoter. Because the green fluorescent bacilli could be directly observed by fluorescence microscopy, the stable expression of GFP was rapid and convenient for conjugation screening in addition to the antibiotic resistance genes within the constructed plasmid. This is the first report on an exogenous plasmid that can be stably maintained as an extrachromosomal element in S. cellulosum. 相似文献
998.
X.Y. Lan S.G. Zhao N. Zheng S.L. Li Y.D. Zhang H.M. Liu J. McKillip J.Q. Wang 《Journal of dairy science》2017,100(6):4294-4299
Contamination of raw milk with bacterial pathogens is potentially hazardous to human health. The aim of this study was to evaluate the total bacteria count (TBC) and presence of pathogens in raw milk in Northern China along with the associated herd management practices. A total of 160 raw milk samples were collected from 80 dairy herds in Northern China. All raw milk samples were analyzed for TBC and pathogens by culturing. The results showed that the number of raw milk samples with TBC <2 × 106 cfu/mL and <1 × 105 cfu/mL was 146 (91.25%) and 70 (43.75%), respectively. A total of 84 (52.50%) raw milk samples were Staphylococcus aureus positive, 72 (45.00%) were Escherichia coli positive, 2 (1.25%) were Salmonella positive, 2 (1.25%) were Listeria monocytogenes positive, and 3 (1.88%) were Campylobacter positive. The prevalence of S. aureus was influenced by season, herd size, milking frequency, disinfection frequency, and use of a Dairy Herd Improvement program. The TBC was influenced by season and milk frequency. The correlation between TBC and prevalence of S. aureus or E. coli is significant. The effect size statistical analysis showed that season and herd (but not Dairy Herd Improvement, herd size, milking frequency, disinfection frequency, and area) were the most important factors affecting TBC in raw milk. In conclusion, the presence of bacteria in raw milk was associated with season and herd management practices, and further comprehensive study will be powerful for effectively characterizing various factors affecting milk microbial quality in bulk tanks in China. 相似文献
999.
The length of small gauge zone (SGZ) between cylinder and flat of a card was studied mathematically. A formula to calculate the length was derived with geometry and calculus methods, by which the abscissa of the point at which the flat–cylinder gauge was minimal was obtained. The effect of heel–toe difference (HTD), cylinder radius, flat setover, minimum flat–cylinder gauge, as well as the difference between outlet gauge and minimum flat–cylinder gauge on the length of SGZ was discussed, respectively. It is concluded that a smaller cylinder radius, smaller HTD and a longer flat setover will help to lengthen SGZ. Given an appropriate value of the difference between the outlet gauge and the minimum gauge, δ, a longer SGZ will be beneficial to improving the carding intensity. But the influence of δ and the minimum flat–cylinder gauge on the length of SGZ can be ignored. The conclusion is of some theoretical value for manufacturers of textile accessories or machinery to accurately choose parameters such as cylinder radius, HTD and setover in production. 相似文献
1000.
Diagnostic Potential of Differentially Expressed Homer1, IL-1β, and TNF-α in Coronary Artery Disease
Xuan Jing Shan-Shan Chen Wei Jing Qian Tan Ming-Xia Yu Jian-Cheng Tu 《International journal of molecular sciences》2015,16(1):535-546
Increasing evidences suggest that inflammation plays an important role in the pathogenesis of coronary artery disease (CAD). Numerous inflammatory cytokines and related genes mediate adverse cardiovascular events in patients with CAD, such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and Homer in the present study. The study was carried out on 163 CAD patients at different stages and 68 controls. The gene expression of Homer1, Homer2, Homer3, IL-1β, and TNF-α in the peripheral blood leukocytes were measured by real-time polymerase chain reaction. The mRNA levels of Homer1, IL-1β, and TNF-α in CAD patients were significantly higher than those in the control group, but not Homer2 and Homer3. However, there was no considerable difference in the mRNA levels of Homer1, IL-1β, and TNF-α among AMI, UAP, and SAP three subgroups of CAD. The receiver operating characteristic (ROC) curves showed that Homer1 had a better diagnostic value for UAP patients compared with IL-1β and TNF-α. Like IL-1β and TNF-α, Homer1 may also be an important participant of atherosclerotic plaque development and eventually rupture. The results of the present study may provide an important basis for diagnosing CAD patients, and provide new therapeutic targets for CAD. 相似文献