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赣南钨矿山资源状况调查与思考   总被引:2,自引:3,他引:2  
通过赣南钨矿山资源调查,反映钨矿山资源状况不容乐观。据地质报告中统计,赣南累计探明WO3储量149.98万t,其中上平衡表113.67万t,而保有储量仅有46.7万t;国有钨矿山保有储量26.4万t,可利用的储量10.4万t,可服务年限大都在10a以下。因此,建议尽快对赣南的国有钨矿山开展新一轮的地质找矿,寻找新的接替基地,控制钨矿产量,对尾砂综合回收和利用。  相似文献   

3.
Drug-associated hemorrhagic colitis are divided into antibiotic associated hemorrhagic colitis (AAHC) and other drug associated hemorrhagic colitis. AAHC are mainly caused by oral usage of Ampicillin and its derivatives (85%). Initially AAHC are believed to be caused by Klebsiella oxytoca overgrowth. However, these organisum has no exotoxin like Clostridium difficile and pathogenesis of AAHC are still unresolved. Typical AAHC are diagnosed by colonoscopy with diffuse hemorrhage and edema mainly found in descending colon and transverse colon. NSAIDs are also the cause of hemorrhagic colitis like AAHC. Mephenamic acid are famous for this complication. Diarrhea is one of the main complication of oral 5-fluorouracil administration and even causes hemorrhagic colitis. Its histology are characteristic in gland atrophy. Gold colitis are reported 36 cases in rheumatoid arthritis patients. Exact mechanism of bleeding are not understood. NSAIDs may cause collagenous colitis and or lymphocytic colitis in RA patients. Other rare hemorrhagic colitis are associated with azathioprine, methyl dopa, interferon alfa etc. NSAIDs and anticoagulants are well known drugs for complication of GI bleeding making hemorrhagic enteritis.  相似文献   

4.
A statistical theory is developed for the decomposition of an amorphous zirconium-palladium alloy in a hydrogen atmosphere with the formation of metal hydrides. The free energies of the phases are calculated, and equations for the equilibrium states of the phases are derived. The phase-transformation temperatures are determined, and their dependences on the system composition are obtained. The temperature dependences of the hydrogen solubilities in the phases are found, and the appearance of the inflection points or jumps at the phase-transformation points, which are experimentally observed as inflections in the dependences, is grounded. Hydrogen solubility isotherms are calculated, and the possibility of a hysteresis effect is revealed.  相似文献   

5.
Draws a distinction between attribution of responsibility for a problem and attribution of responsibility for a solution. Four general helping models are derived. In the "moral" model, actors are held responsible for both problems and solutions and are believed to need only proper motivation. In the compensatory model, people are responsible only for solutions and are believed to need power. Individuals in the medical model are responsible for neither problems nor solutions and are thought to need treatment. In the enlightenment model, actors are responsible for problems but are unable or unwilling to provide solutions; they need discipline. It is maintained that each set of assumptions has characteristic consequences for the competence, status, and well-being of actors and that the wrong choice of model in a situation will undermine effective helping and coping. Competing models of responsibility in education, psychotherapy, law, and welfare are described, and research on attribution of responsibility is recommended as a way of addressing problems of both theoretical and social significance. (128 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Methods of producing nanopowders and consolidated powder nanomaterials are reviewed. Various methods of nanopowder production are analyzed, and the properties of nanopowders are presented. Consolidation of nanopowders by pressing, sintering, and pressure sintering is discussed. The properties of consolidated powder nanomaterials are presented. The prospects for their application as constructional, functional, and high-energy materials are assessed.  相似文献   

7.
The genetic algorithm (GA) is a general optimization technique that has some unique features that are especially suitable for structural engineering problems. This work uses a simple GA with elitism to find the optimum design of welded steel plate girder bridges. The objectives are to minimize the weight and the cost of the girders. Two types of plate-girder bridges are studied: a single-span bridge and a two-equal-span continuous bridge. Bridges with various span lengths, in increments of 20?ft, are investigated; results are tabulated, parametric studies are made, and meaningful conclusions are drawn.  相似文献   

8.
Recommendations are made regarding risk reduction when investing in intellectual property. The low level of investment by metallurgical enterprises in intellectual property is explained. Methods of logical research, analysis, synthesis, and planning are employed. Approaches to strategic risk management in innovative metallurgical investment are outlined. The preconditions for innovation in metallurgical development worldwide are discussed, and corresponding innovative development strategies are formulated. Methods of risk reduction are formulated, and practical examples of investments in intellectual property that might be more attractive to metallurgical enterprises are presented.  相似文献   

9.
无缝钢管中非金属夹杂物特性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
峰位于4869 eV位置,对应于元素锡的四价氧化态。锡泥中含有的主要成分为SnO2。  相似文献   

10.
Anomalous intestine positions arise during embryologic development. They are rare in adults and cause uncharacteristic but chronic discomforts. They can produce life-threatening complications at any time. They are thought of too rarely, and radiologically shown anomalies are easily misinterpreted. Frequently they are discovered only during operation. The 178 anomalous intestine positions are here analyzed partly newly named and discussed to facilitate detection, to prevent complications, and to make rational treatment possible. There are 24 different typical forms, which are explained by disturbances of the embryologic rotation, growth, or fixation of the intestine.  相似文献   

11.
王广成  任满杰 《黄金》2001,22(12):47-51
文中分析了资源-环境-经济一体化核算的研究现状及存在的问题,界定了矿产资源核算的内涵及其对象,论述了矿产资源定价的理论基础,探讨了矿产资源的各种定价方法及其优缺点,适用范围,建立相应的估价模型,并进行了实证分析,这项研究对我国的资源--环境-经济一体化核算的理论研究与实践进展具有重要的理论意义和现实意义。  相似文献   

12.
胡建梅 《山西冶金》2001,(2):7-8,22
针对推标工作的指导思想、基本原则、基本步骤、具体做法、实施措施、工作速度,制定了有效办法,保证了推标工作的有序进行,克服了推标工作的随机育目性,在岗位操作标准制定时,打破以往三大进修规程的理论体系强,岗位操作弱的特点,抓典型、树样板、以点带面、以面推动全局。  相似文献   

13.
任安超 《钢铁》2011,46(1):92-92
 客运专线用100米60kg/m重轨在焊轨厂拼焊后,当四面矫直时发生断裂。采用光学显微镜及扫描电镜(TEM)等方法对钢轨矫直时断裂原因进行了分析和研究。结果表明:钢轨断裂是由于距钢轨端部约100mm轨底边缘处存在凸台缺陷,此凸台在钢轨拼焊后进行除瘤时除瘤刀将其铲平,致使钢轨产生冷裂纹,进而在矫直时断裂。通过控制万能精轧上下辊的辊径差以及调整轧制线高度等方面,使钢轨出轧机时尽量保持平直,避免上翘或扣头,从而消除凸台缺陷的产生。  相似文献   

14.
中国锰系铁合金现状与发展   总被引:1,自引:0,他引:1  
严旺生 《铁合金》2003,34(6):35-39
介绍了世界、中国锰系铁合金生产、消费和进出口情况,分析了锰系铁合金的需求发展与变化,预测了2003年中国锰系铁合金消费、出口与生产情况,展望了2005年中国锰系铁合金的消费需求,提出了发展建议。  相似文献   

15.
The problem of defining satisfaction and the difficulties in distinguishing interests and satisfactions are indicated. "Aside from the final, consummatory activity, satisfaction cannot be identified in terms of activities, as can interests… . Because opinion items are not as stable as interest items, it is doubtful that they can be as useful as interest items in predicting future behavior." 5 characteristics of interests are that they: are acquired, are persistent, vary in intensity, function in acceptance-rejection behavior, are indicated in readiness to act. "Interest tests are diagnostic because no two persons have acquired the same lists of activities nor are the activities classified in the same manner as liked or disliked. Moreover, people engaged in an occupation have to a marked degree similar interests, and so people in one occupation can be differentiated from members of other occupations." Major topics are: job satisfaction and job success; opinion, attitude, interest, and satisfaction; measurement of motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
The unsteady motion of streams, with a free surface, has been described by a system of equations that were proposed by Saint-Venant in 1871. These are universally known as “Saint-Venant’s equations.” Weighted four-point implicit finite difference schemes are largely used for their numerical solution in the case of one-dimensional flow. For these models, stability, dissipation, and dispersion are first investigated by looking at the truncation error and then by using Fourier’s classic linear analysis. Variations of the space and time weighting coefficients, the Courant number, the Froude number, and the frictional resistance term are examined in this paper. In particular, instabilities are analyzed that are due to the progressive accumulation of dispersion errors, which are the consequence of an increasing frictional resistance term. However, in this case the numerical scheme requires a dissipation mechanism. Computational suggestions are given for this mechanism.  相似文献   

17.
《粉末冶金学》2013,56(6):160-169
Abstract

The processes involved in the production of dense ceramics from powder materials by the simultaneous effect of pressure and heat at temperatures above 1500°C are outlined. The factors leading to the choice of this method of fabrication, and the general principles involved in hot pressing, are first dealt with, and the advantages and disadvantages of the process are then discussed. Current techniques are described and their limitations considered. Examples of typical applications are given, and possible lines of future development are indicated.  相似文献   

18.
陈巍  方会斌  秦文 《冶金能源》2007,26(3):39-42
论述了蓄热式钢包烘烤器的设计关键,计,介绍该技术在首钢第二炼钢厂的应用效果,办法。即烧嘴的设计、蓄热室的设计和换向阀的设并对存在的问题进行分析,初步找到了解决  相似文献   

19.
Biological effects of reactive oxygen species and other radicals which are controlled by antioxidant mechanism are exerted on the basis of enzymes and substrates. Antioxidant substrates are divided into lipophilic and hydrophilic groups. Main representants of lipophilic antioxidants are retinol and tocopherol which are closely related to ascorbate in the hydrophilic compartment. Described methods for detection of retinol and alpha-tocopherol are simple, sensitive, specific and precise. They are reliable, economic and fast. Only small amounts of serum are used for one analysis which is convenient for patients, too. Our methods can be recommended for routine use in laboratories of clinical biochemistry. Haemodialyzed patients, retinol serum level was higher than that in blood donors while alpha-tocopherol serum level did not differ. Both vitamin A and E serum levels were similar in alcoholics compared to controls.  相似文献   

20.
介绍了采用铁水脱硫预处理、复吹转炉、LF精炼、RH精炼、板坯连铸工艺开发X80管线钢的过程。采用该工艺生产的X80管线钢钢水成品[C]≤0.05%[,P]≤0.012%[,S]≤0.0022%[,N]≤0.005%,T[O]≤30×10-6,[H]≤2.5×10-6,钢中的A、B类夹杂物控制在1.5级以下,C、D类夹杂物能控制在0.5级以下,管线钢洁净度完全满足用户要求。  相似文献   

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