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31.
今年上半年我国石油工业基本保持平稳、健康的发展格局:油气产量和消费需求均持续增长,油气开采业大幅盈利,原油加工业仍然亏损,投资大幅度增长,原油进口依存度加大。下半年需要采取的应对措施是:进一步完善成品油价格形成机制;规范和引导上海石油交易所健康运行;加强天然气管理,作好需求预测;实施石油替代激励政策。预计下半年国际油价继续走高的可能性较大;我国全年石油表观消费可能会突破3亿吨,进口依存度继续在40%以上。  相似文献   
32.
中国古陶艺制品造型,釉色,装饰等艺术符号都与每时期的阶段性精神和物质生活相联系,但在"现代艺术"文化认识领域中,往往从理论思维角度把陶艺实用目的的物质性排斥在文化范畴之外。艺术常常强调物质的观赏性,而陶艺的实用功能就是这种文化类型的主体,陶艺的文化性和功能性,具有实用和审美文化的高度叠合,永久地承载着实用功能和精神功能两大内容。  相似文献   
33.
激电法找油的原理及应用   总被引:1,自引:0,他引:1  
激电法是非地震物探手段中的一种,由于油气在向上渗透的过程中会与地层发生一系列的生物。化学反应而形成次生黄铁矿,激电法正是通过发现油气藏上方形成的次生黄铁矿晕来寻找油气的一种间接找油方法。通过详细介绍激电法寻找油气的基本原理。仪器设备等,从实践角度论述了激电法在油田勘探开发中的应用范围及其特点,最后通过兴例说明了其良好的应用效果。  相似文献   
34.
A novel strategy of sweep coagulation to treat low turbidity water is presented herein. Study findings demonstrated that an Na+‐saturated bentonite with medium cation exchange capacity (CEC) resulted in significant turbidity removal at a bentonite dosage of 30 mg dm?3. Bentonite dispersion with fully delaminated platelets tended to undergo a more porous type of coagulation with intense face‐to‐face interactions of platelets and effectively entrapped TiO2 particles in band‐type structures. This type of coagulation usually results in a large volume of settled flocs with a fluffy structure and excellent turbidity removal efficiency for sweep coagulation. The sign and magnitude of electrical charge on TiO2 particles has a minor effect on the efficiency of sweep coagulation. Copyright © 2005 Society of Chemical Industry  相似文献   
35.
杜雪梅  吴云  满拥军 《包钢科技》2003,29(6):85-86,98
为了能及时了解放射性工作人员的受照剂量,以便能够更好地保障放射工作人员的健康与安全,采用热释光测量法对包头地区从事放射性工作的工作人员进行了个人剂量监测,并对他们的剂量当量频数分布进行了统计与分析,对工作环境的防护进行了调查对比,就今后的工作提出建议。  相似文献   
36.
徐高 《有色设备》2004,(Z1):80-82
针对熟料饲料油隔泵供料压力不稳定、消耗油及备件量大、检修频繁的情况,着重介绍和探讨了对新型离心泵的选型、可行性分析、过流件材质及密封的选择、新型饲料泵的成功应用.  相似文献   
37.
The SSC GEM silicon Central Tracker design incorporated 18-cm long single-sided AC-coupled silicon microstrip ladders. Compared to the 12-cm long ladders considered in the preliminary stages of the tracker design, the 18-cm long ladders have the advantage of reduced cost, channel count and overall power consumption, and led to a simplified tracker assembly. However, such long ships also present the challenge of maintaining satisfactory performance. The increased capacitance and series resistance contribute to lower signal-to-noise ratios, longer time walk, higher power consumption per channel and increased probability of crosstalk to neighboring channels. In this paper, an accurate method to calculate the geometric capacitance of the AC-coupled microstrips is presented and the calculated results are compared with measurements, SPICE simulations are performed to predict the noise, the extent of interstrip capacitive coupling and the dispersion of the detector signal due to the finite series resistance of the metal strips and the long length of the detector. The influence of the preamplifier current and the shaping time on the signal and noise levels is also presented. The study concludes that the 18-cm long ladders can successfully satisfy the performance goals of the GEM silicon Central Tracker  相似文献   
38.
39.
Polymorphonuclear leucocyte (PMNL) accumulation in extravascular tissues and inflammatory exudates is dependent on their migration through blood vessel endothelium and then through connective tissue. Previously we utilized a barrier of human synovial and dermal fibroblasts (HSF or HDF) grown on microporous filters, as a model of PMNL migration through connective tissue. Those studies showed that beta 2 (CD18) and the beta 1 integrins, very late activation antigen-5 (VLA-5) and VLA-6, in part mediate this PMNL migration. Here we report that VLA-4, which can also be expressed at low levels on activated PMNL, is also involved in PMNL migration induced by C5a through fibroblast (HSF and HDF) barriers, because monoclonal antibody (mAb) to VLA-4 significantly inhibited (by 20-30%) PMNL migration. Blocking the function of CD18, VLA-5 or VLA-6 was not required for detection of the VLA-4-mediated migration. Combination treatment with mAb to VLA-4 and with mAb to VLA-5 or to VLA-6 further inhibited PMNL migration, irrespective of whether CD11/CD18 mechanisms were blocked with anti-CD18 mAb or not. Treatment of PMNL with a peptide based on the VLA-4-binding domain in the CS-1 fragment of fibronectin, but not a control peptide, inhibited PMNL migration to a comparable extent to treatment with mAb to VLA-4. A low level of VLA-4 was expressed on C5a-activated PMNL, detected by immunofluorescence flow cytometry. These results suggest that VLA-4 can be mobilized by human peripheral blood PMNL and can, in addition to VLA-5, VLA-6 and CD11/CD18 integrins, mediate PMNL migration through connective tissue. This is in marked contrast to PMNL transendothelial migration, where beta 1 integrins appear to play no significant role.  相似文献   
40.
Presents here a complete dynamic model of a lithium ion battery that is suitable for virtual-prototyping of portable battery-powered systems. The model accounts for nonlinear equilibrium potentials, rate- and temperature-dependencies, thermal effects and response to transient power demand. The model is based on publicly available data such as the manufacturers' data sheets. The Sony US18650 is used as an example. The model output agrees both with manufacturer's data and with experimental results. The model can be easily modified to fit data from different batteries and can be extended for wide dynamic ranges of different temperatures and current rates.  相似文献   
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