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91.
针对岩石受荷载变形的电阻率变化、各向异性变化等现象的分析,目前大多为实验分析和理论研究,通过井下综合物探技术对井下高应力集中区的分析研究较少。着重介绍了在煤矿超前探测中,遇到高应力集中区时,采用瞬变电磁法和雷达进行综合物探的方法和过程,以及如何进行打钻验证,为相关的实验分析、理论研究提供实例依据和支撑。 相似文献
92.
自动化立体仓库最大限度利用空间,最大限度地满足生产要求,减轻工人劳动强度,提高生产效率,加强生产和物资管理,减少库存积压资金等方面具有无可比拟的优势,这正是一个现代化企业所要求的和追求的。由于采用计算机管理和网络技术,使企业领导宏观快速地掌握各种物资信息和使工程技术人员、生产管理人员、生产技术人员及时了解库存信息以便合理安排生产工艺、提高生产效率成为可能。综观国内外的大型企业,自20世纪60年代始逐步采用自动化物流系统以来,到今天已成为企业生产管理不可缺少的重要组成部分。建立自动化立体仓库系统已成为现代化企业的重要标志之一。 相似文献
93.
根据云南省"城镇上山"政策,针对开远市特殊的地形,提出退台式山地特色工业园区开发模式。根据现状地形分析,分析了退台式开发模式的优势,对工业厂房、物流仓储的退台式效果进行了分析研究。 相似文献
94.
根据挤扩支盘桩的成桩工艺,基于该桩的现场静载荷试验数据,对挤扩支盘桩的承载性能及影响因素开展了研究。基于对挤扩支盘桩的数值计算,研究了扩底桩的竖向承载性能和荷载传递机理,分析了等直径桩和扩底桩承载特性的异同。采用有限差分数值方法建立基本计算模型,对桩长、桩径、扩底次数、扩底桩径、桩身模量等影响单桩承载性状的因素进行了分析研究。 相似文献
95.
Xun Cao Rui Zhang Wei-min Tan Ce Wei Jing Wang Ze-meng Liu Ke-quan Chen Ping-kai Ouyang 《Korean Journal of Chemical Engineering》2016,33(5):1653-1658
Plasma-modified multiwalled carbon nanotubes (MWNTs) were used as a support to immobilize lipase. The effects of vacuum plasma treatment power, vacuum plasma treatment time, immobilization temperature, immobilization time, and initial protein concentration of the lipase on the amount of lipase immobilized and on the subsequent activity of the immobilized lipase were investigated. The results showed that the adsorption capacity of the plasma-modified MWNTs could reach 0.15 g/g and that the maximal enzyme activity of the immobilized lipase was 520U/g under optimized conditions. Fourier transform infrared (FTIR) analysis and transmission electron microscopy (TEM) were used to characterize the properties of the plasma-modified MWNTs and plasma-modified MWNTs-lipase, and the results showed that the lipase was successfully immobilized on the plasma-modified MWNTs. Also, the MWNTs-lipase produced an esterification rate of approximately 47% in the synthesis of polyethylene glycol (PEG)-aliphatic esters. 相似文献
96.
97.
通过对材料成分、熔炼工艺、浇注工艺及热处理工艺的合理选择,制备出塔式搅拌磨机用高铬合金铸铁衬板,同时系统地对其硬度、冲击韧性、淬透性及耐磨性进行了研究.结果表明:通过材料成分及生产工艺的优化,可生产出硬度达HRC60以上、冲击韧性好、淬透性好的高铬铸铁衬板;其耐磨性是高铬铸铁Crl5的1.46倍、是高锰钢Mn13的2.11倍;性价比远高于同类进口产品,可取而代之并得到推广应用. 相似文献
98.
Johan R. C. van der Maarel Ce Zhang Jeroen A. van Kan 《Israel journal of chemistry》2014,54(11-12):1573-1588
The study of nanochannel-confined DNA is important from biotechnological and biophysical points of view. We produce nanochannels in elastomer with soft lithography and proton beam writing. Issues concerning DNA confined in such quasi one-dimensional channels are discussed. We describe DNA stretching via the control of channel diameter and buffer conditions and how the extension can be interpreted with theory and computer simulation. We then discuss the conformation of nano-confined DNA crowded by neutral polymers and like-charged proteins. As an example of a protein that has an affinity to DNA, the effect of heat-stable nucleoid-structuring protein, H-NS, on the folding and compaction of DNA is reviewed. Compaction of DNA by eukaryotic protamine and unpacking of pre-compacted DNA through an increase in salt concentration are discussed. We review results obtained with a novel, cross-channel device that allows the monitoring of the dynamic, conformational response of DNA after exposure to a ligand or protein and/or a change in buffer conditions in situ. As a biotechnological application, linearization of DNA by bottlebrush coating with a polypeptide copolymer is discussed. It is demonstrated that large-scale genomic organization can be sequenced using single DNA molecules on an array of elastomeric nanochannels. Overall, our results show that the effects of ligands and proteins on the conformation, folding, and condensation of DNA are not only related to classical controlling factors, such as osmotic pressure, charge, and binding, but that the interplay with confinement in a nanospace is of paramount importance. 相似文献
99.
Acrylate–vinylidene chloride copolymers derived from corresponding water‐borne latexes: Influence of acrylate units on their potential as heavy‐duty anticorrosive coating materials 下载免费PDF全文
A series of aqueous latexes with solid contents of 56%–59% were synthesized by binary emulsion copolymerization of vinylidene chloride (VDC) with an acrylate, namely methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), hexyl acrylate (HA), or 2‐ethylhexyl acrylate (EHA). Differential scanning calorimetry (DSC) and Fourier‐transform infrared (FTIR) spectroscopy showed that the acrylate units with short ester side‐chains, such as MA and EA, made the copolymers hard and the crystallization tendency of their PVDC segments was reduced. Hydrophobic acrylates with relatively long ester groups, such as HA and EHA, gave flexible copolymers, and favored the crystallization of their PVDC segments. BA endowed the copolymers with medium flexibility and crystallization tendency. As coating materials, the copolymers bearing MA and EA adhered poorly to the tinplate before or after 100 hr of salt‐spray corrosion, whereas those bearing BA, HA, or EHA showed good adhesion to tinplate when they had little or no crystallinity. After 100 hr of salt‐spray corrosion, only BA–VDC80, containing 80% VDC, retained both excellent adhesion to metal and excellent barrier performance. Further study demonstrated that BA–VDC80 could protect tinplate from rusting for at least 250 hr under harsh salt‐spray corrosion. Scanning electron microscopy, FTIR‐attenuated total reflectance spectroscopy and DSC were used to evaluate the corroded BA–VDC80 film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40192. 相似文献
100.