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951.
以电子商务提升服装行业核心竞争力为切入点,提出“动态整合联盟、电子商务平台构建设想,并从服装企业供应链角度阐述了该构想在网站建设方面的具体实施方案,最后总结了该构想塑造的服装行业电子商务所具有的竞争优势。 相似文献
952.
本文以多数据源的中文报表为研究对象 ,运用面向对象的方法 ,对其组成结构进行分析 ,提出了中文报表的生成四要素 ,并根据其数据来源的种类、限制条件、统计条件、各种综合条件以及各种相关的处理情况 ,从理论上提出报表单元格内容定义生成的解决方案 相似文献
953.
Loess in the Tian Shan and its implications for the development of the Gurbantunggut Desert and drying of northern Xinjiang 总被引:8,自引:0,他引:8
Xiaomin Fang Zhentao Shi Shengli Yang Maodu Yan Jijun Li Ping’an Jiang 《科学通报(英文版)》2002,47(16):1381-1387
Eolian loess is widely distributed on the various geomorphic surfaces between 700–2400 m a.s.l. on the northern slope of the
Tian Shan. It is formed in a synchronous manner with dust transported from the Gurbantunggut Desert in the Junggar Basin.
The thickest section of loess was found in the Shawan and Shihezi regions. Paleomagnetic and climatic proxy analyses of over
71 m of a loess-paleosol sequence on the highest terrace of the Qingshui He (River) in the Shawan show that the paleomagnetic
Bruhues/Matuyama (B/M) boundary lies at the bottom of paleosol S8, at a depth of 69.5 m, and the bottom of the sequence was
estimated to be ∼0.8 Ma. This implies that the extremely dry climatic conditions in the Junggar Basin and the initial Gurbantunggut
Desert were present at least by 0.8 Ma. High-resolution grain size series demonstrate that this area and desert expansion
experienced two dramatic periods of desert expansions that occurred at ∼0.65 Ma and 0.5 Ma, respectively; and the subsequent
continuous enhancement led to the environment presently observed. This tremendous environmental effect, caused by large-scale
expansion of the desert and arid region of inner Asia, might be an important driving force for the global temperature drop
that occurred in the mid-Pleistocene. 相似文献
954.
PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County,Inner Mongolia: Indicator to source of metallogenic elements 总被引:1,自引:0,他引:1
By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit,
we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of
sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite,
arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle lherzolite, and others resemble
the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains
or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from
the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived
magma also offered some elements. 相似文献
955.
Weijuan Zhao Aijun Xu Rongwu Li Zhengyao Gao Guoxia Li Jianzhong Xie Guohe Han Songlin Feng Dongyu Fan Ying Zhang Zhifang Cai Zhongli Zhang Junxiao Zhu 《科学通报(英文版)》2002,47(16):1337-1340
In order to search for sources of the raw material of the Qin’s terracotta warriors and horses, we selected 20 samples of
pottery warriors and pottery horses of the Qin’s Mausoleum from pit No. 1, 19 samples of pottery warriors and brick from pit
No. 2, 20 samples of clays near the Qin’s Mausoleum and 2 samples of Yaozhou porcelain bodies. The 32 kinds of element content
of each sample were measured by neutron activation analysis (NAA). These data were analyzed by fuzzy cluster analysis, the
trend cluster analysis diagram was obtained. The results showed that samples of terracotta warriors and horses from pits No.1
and No. 2 were closely related to the loam layer near Qin’s Mausoleum, but their relations with the loess layers were not
so close, and they were out of all relation to Yaozhou porcelain bodies. Thus, it could be deduced that the Li Mountain clay
may be considered as the original place of the raw materials of the terracotta warriors and horses, the kiln sites might be
located nearby the Qin’s Mausoleum. 相似文献
956.
Thermoelectric power (S) measurements have been systematically investigated in high-quality La2-x-Srx-CuO4 single crystals with different Sr concentrations (x =0.03, 0.05, 0.07, 0.1, 0.12). In this doping range studied, S remains positive, and with the increase of Sr concentration,room-temperature thermoelectric power S (290 K) decreases.An empirical formula which presents a relationship between hole concentration P and room-temperature thermoelectric power S (290 K) is reported in this note. Based on the theory of metallic diffusion model, the experimental results are discussed. 相似文献
957.
Intensity index series of Subtropical High over the Western Pacific was constructed according to modeling results by using of CCM3.6 atmospheric model with climatologically SST forcing for 30 years, and with observed SST forcing from 1900 to 2000. The index series constructed by modeling closely correlated to the observations for 1951-1999 (c.c. 0.72) and to the statistically reconstructed one for 1900-1950 (c.c. 0.51). The index series for 1900-1999 showed significant 80 a and 40 a periodicity. A minimum of persistence in seasonal variations of the index occurred in Autumn, which was called "Autumn Barrier". It may relate to the "Spring Barrier", found in the seasonal variations of SST over the Eastern Equatorial Pacific. The increasing trend shown in the index series for the 20th century may associate with the global warming caused by enhancement of greenhouse effect. 相似文献
958.
Construction of multivalent DNA vaccines forMycobacterium tuberculosis and its immunogenicity 总被引:1,自引:0,他引:1
The coding regions of Ag85B MPT-64, and ESAT-6 secreted proteins were cloned initially into the eukaryotic expression vector pJW4303, then transformed to E. coli Top 10 strain for plasmid DNA extraction and further analysis. Plasmids containing the right insertion were sequenced to confirm their identity. COS7 cells were transfected with a mixture containing serially diluted plasmid DNA encoding three secreted proteins and Lipofectin (Gibco). The supernatants and pellets prepared from various cell lines were run on SDS-PAGE gel and the expression of these proteins in COS7 cells were demonstrated by immunoblot using polyclonal or monoclonal antiserum of M.TBH37Rv. 21 days after first vaccination of C57BL-6 mice by all three recombinant eukaryotic expressing vectors, antibody titer for Ag85B reached 1∶3200. 21 days after second vaccination, the antibody titer reached 1∶102400. The highest antibody levels induced by multivalent vaccines after the second injection were equal to or even greater than the highest antibody levels of single DNA vaccine reported in literature after third injections. Antibody titer of MPT-64 was 1∶50 after the first injection and it reached 1∶200 after the second injection. No antigen-specific antibody against ESAT-6 was detected in sera harvested from immunized mice 21 days after both injections. Antigen-specific IFN-g level of Ag85B was 110 pg/mL while no antigen-specific IFN- g level of ESAT-6 and MPT-64 was detected even after third injections. To our knowledge, it is the first time that studies of polyvalent recombinant DNA vaccines against TB were carried out in C57BL-6 mice. Our results indicated that multiple DNA vaccines could be used to enhance protective responses against M.TB. 相似文献
959.
In MRI (Magnetic Resonance Imaging), a crucial role of gradient coils is to image organism, meanwhile the inductance of the coils determines the speed of imaging. So it is of great importance to optimize designs of the gradient coils. The target field approach is an effective method to design the gradient coils. Having applied this method and performing many numerical tests, we achieved the designs of the x-、y-、z- gradient coils , with the linearity of the fields generated by the coils in a sphere of radius 0.30 m less than 5%, in which the inductance and resistance of the coils also meet the requirements. 相似文献
960.
转杯纺自由纱段形态对其捻度分布的影响 总被引:1,自引:1,他引:1
通过对自由纱段的运动及受力分析,对自由纱段形态以及纺纱工艺参数对自由纱段捻度分布的影响进行了研究。研究表明:因自由纱段在杯内成弯曲形状,从而使得自由纱段捻度自假捻盘入口处向剥离点处不断减少,真至剥离点处纱条捻度甚至降到只有设计捻度的40%-80%。为了保证凝聚槽内一定的捻度传递长度,则须适当提高设计捻度,这就揭示了转杯纱设计捻度高于环锭纱的一个主要原因。高速细支时的剥离点纱条捻度相对于低速粗支而言要高,说明只要一些纺纱工艺参数如转杯直径、转杯速度、假捻盘规格等配合得当,转杯纺也可高速稳定地纺制细支纱。 相似文献