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杨金平 《中国钼业》2005,29(3):52-54,56
市场定位是企业营销战略的一个重要环节,企业通过细分市场,选择合理的目标市场,发掘市场机会,针对性开展市场营销活动。  相似文献   

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李英龙  李柏林  李文瑶 《黄金》2001,22(6):48-50
文中在对矿业权市场要素进行分析的基础上,提出我国矿业权市场模型,并对其进行了分析。  相似文献   

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《铁合金》2007,38(3):5-5
近日国内铬矿价格持稳,高品位报价仍为73~75元/铬,但由于南非铬矿进口量增长,港口报价有小幅度的调整,前期报价已经达到了55~56元/铬,可近期有所缓解在50~53元/铬左右。随着南非矿进口的增加,业内人士认为南非进口量有可能会取代印度矿的位置。从今年1~4月份我国累计进口南非铬矿48万t,较去年同期增长200%(16万t);然而今年3月份开始印度提出征收出口关税,  相似文献   

7.
1999年钼市回顾与2000年钼市展望   总被引:5,自引:5,他引:0  
王顺昌 《中国钼业》2000,24(3):50-53
回顾了1999年世界钼市的状况并展望了2000年世界钼市的前景。  相似文献   

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烨联及唐荣开出的7月份新盘价大幅调降,300系热冷轧均调降28000新台币/吨,以反应镍价重挫,这也是近5年跌幅最深的一次。[第一段]  相似文献   

9.
预计2005年稀土价格将进一步上涨。其中主要是需求激增的Nd—Fe—B磁体原料Nd、Pr、Dy等。由于中国江苏和内蒙古包头市的精矿及萃取分离等大企业联合实行减产、停产和涨价等措施,2004年开始稀土价格迅速上涨。2004年初中国资源较少的Dy、Tb分别比2003年末上涨了309,6和609,6,Nd上涨了79,6(以上均为金属)。之后,虽然没有大幅度上涨,但行情逐渐走高。2004年底,Nd为9美元/Kg,Dy为50美元/kg(80Dy-20Fe母合金),Tb为400美元/kg。  相似文献   

10.
重点分析了钛白粉产品市场现状及其市场发展前景,并在市场分析的基础上,对未来我国钛白粉产业的发展提出建议。  相似文献   

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The objective of the study is, on one hand, to determine the etiology and the clinical implications as a function of the isolated germ, of central venous catheterization in patients with parenteral nutrition in our hospital, and on the other hand, to determine which factors are associated with the selection of germs of central venous catheterization in parenteral nutrition. For this we included venous catheters, colonized for 5 years, and with a study of the different segments (connection, insertion point, and tip). As a function of the appearance of associated clinical symptoms, of the results of the blood culture, and of the clinical evolution of the patient, the variables which determine the level of pathogenicity of the different groups of germs in the central venous catheterization, are defined; for the study of the factors associated with the selection of the different groups of germs, 8 variables were chosen. The data obtained are statistically treated, and the results are considered to be significant if p < 0.05. The understanding of the different factors associated with the selection of germs, and the level of clinical pathogenesis of the different groups, allows a better level of the clinical action in the prevention of the infection associated with the catheter.  相似文献   

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This work offers an overview of the state of the art and future state of environmental health in our country from a viewpoint of the impact of the commercial opening established in the Free Trade Agreement among Mexico, the USA, and Canada. In the first section of this work, we analyze the expected economic changes resulting from the implementation of the FTA and foretells the way in which those changes will influence the present environmental and epidemiologic profiles of this country in the medium and long term. The main changes predicted by the analysis are, in the epidemiologic context, the acceleration of the transference of occupational, consumption, environmental and population risks, characteristic of industrialized countries, to the country's polarized epidemiologic profile; and, in the environmental context, a transition consisting of a broadening and composition of the spectrum of pollutants, including and important lagging of bacteriologic control. The second section offers an analysis of the predicted response capacity facing the new environmental risk dynamics in the country, encompassing regulation, normativeness and enforcement of environmental and consumer protection, as well as obstacles found in health services to the implementation of surveillance, detection and treatment of health damages caused by environmental factors. The analysis of the organized social response to these problems discloses a relative flexibility of the normativeness and enforcement functions in comparison with our northern neighbors, a paramount factor for the possible transference of environmental risks, as well as the informational and research deficiency about environmental issues, basic elements for sustaining environmental health in the country, aiming at speeding up the development and transference of technologies for prevention, detection and management of environmental risks in the country, drawing upon the systematization of our experience and that of our neighbors. This speeding process ought to match, in the medium term, the velocity of risk transference produced by the commercial opening. In this way, the commercial integration of North America will become a favorable context for the development of the environmental health infrastructure of the country.  相似文献   

13.
《粉末冶金学》2013,56(5):45-63
Abstract

Large volume expansions accompany the formation of binary alloys of beryllium with uranium, thorium, iron, copper, zirconium, titanium, and vanadium, and of uranium with aluminium, during the sintering of the mixed, cold-compacted elemental powders. No expansion was detected during the sintering of binary mixtures of beryllium with aluminium, silicon, and magnesium, or mixtures of uranium with zirconium, molybdenum, iron, nickel, manganese, and chromium.

When it occurs, expansion is anisotropic, being greatest in the direction of compacting; the degree of anisotropy varies with the constituents and the composition of the alloys. In systems undergoing expansion, the volume expansion/composition graphs exhibit maxima. For a given system the magnitude of the maximum is a function of the shape of compact, the particle size of the powders, and the sintering time and temperature; the composition at which the maximum occurs is sensibly unaffected by these latter variables.

These experimental observations, together with those of other investigators, can be satisfactorily interpreted on the hypothesis that volume expansion is due to the formation of diffusional porosity during sintering.  相似文献   

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为了阐明银含量对方铅矿浮选的影响,提高含银方铅矿中伴生银的综合回收效率,通过全面梳理前人研究成果,对含银方铅矿的资源状况、工艺流程和药剂制度进行了总结。首先,从不同维度和层面(从试验到模拟、从宏观到微观)综述了银含量对方铅矿的影响,其中包括银含量对方铅矿浮选行为及表面接触角的影响。然后,评述了前人利用红外光谱、微热动力学、电化学和量子化学等分析方法开展的有关银含量对方铅矿浮选行为影响机理的研究进展,上述分析方法相互验证,均证实银矿物对方铅矿的浮选有促进作用,且银含量与促进程度呈正相关。最后,针对含银方铅矿今后研究方向和银铅锌矿资源开发,提出科学、合理的建议,如:在现场生产中应尽量避免使用石灰调浆,如必须使用时,应控制好石灰用量,从而减少伴生银的损失。  相似文献   

15.
火焰原子吸收光谱法测定合金结构钢中铬、锰   总被引:1,自引:0,他引:1  
利用火焰原子吸收光谱法测定合金结构钢中铬、锰,此方法快速、准确、灵敏度高、精密性好,方法简便,并充分反应了现代仪器的高科技分析手段。合金结构钢使用较为广泛,因此利用原于吸收光谱法测定铬、锰,能迅速有效的达到检测目地的需要。本方法改变了以往化学法操作时间长、步骤多、消耗试剂多的弊病,解决了高氯酸氧化铬对人体的危害及对环境的严重污染。通过对各项做条件试验,优选了最佳仪器测试条件。对干扰元素铁、镍抑制铬的吸收,采用硫酸钠做干扰消除剂,彻底消除了干扰,测定数据稳定可靠。经过对标准样品的测定,重复性好,误差小,回收率达到99~102%,效果令人满意。  相似文献   

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Many artists have used the symbol of salt in both religious and profane works, yet very few studies have explored the symbolism of salt as used in works of art. In this study, Panofsky's method has been adopted to evaluate works of art through an organic process articulated into three stages: (1) pre-iconographic, (2) iconographic and (3) iconological. The method was used for (a) religious paintings of the Old and New Testaments and (b) mythological and profane themes. Various salt-cellars were also studied. In particular, the paper examines the following themes: Isaac blessing Jacob, the return of Esau, Samuel consecrating David, the Last Supper, the suppers at Emmaus and at the house of Simon, the birth of St. John the Baptist, the Baptism of Constantine, the prodigal son, Bacchus-Apollo, the nuptial banquet of Love and Psyche, the death of the Cavalier of Celano, the king drinks, the landlord's visit, 'Phitopolis faisant servir des mets en or au roi Pithès', certain still life paintings and various salt-cellars including those of Cellini and Giulio Romano. The paper discusses the works of many artists including Raphael, Leonardo and his school (Boltraffio, Giampietrino, d'Oggiono, Solario), Hendricksz, Corenzio, Jean-Baptiste and Philippe de Champaigne, Damaskinos, Tintoretto, Titian, Romanino, Rubens, Bellini, Bloemaert, Veronese, Sustris, Just of Ghent, Jan Van Hemessen, Poussin, Loir, Giotto, Jordaens, Brueghel and Mimmo Paladino with his enchanted mountain. From the data examined it emerged that salt is a primary iconological presence in various works of art.  相似文献   

17.
To elucidate the accumulation of calcium in the human arteries, the calcium contents of the thoracic aorta, coronary, common carotid, basilar, internal thoracic, axillary, radial, femoral, popliteal, and dorsalis pedis arteries, were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The calcium content began to increase in both the thoracic aorta and femoral artery around the age of 50 years (yrs), in the popliteal artery at the age of 60 yrs, in the coronary, basilar and dorsalis pedis arteries at the age of 70 yrs, and in the common carotid artery at the age of 80 yrs. In the same time, the calcium content did not increase significantly in the internal thoracic and radial arteries. Accumulation of calcium in human arteries was classified into two groups: The first is an age-related increase of calcium content in the arteries like the thoracic aorta, coronary, common carotid, basilar, axillary, femoral, popliteal and dorsalis pedis arteries. The second is non-age-related, such as the internal thoracic and radial arteries. To examine the localization of this calcium accumulation, the thoracic-aortic and femoral-arterial walls were separated into the three tunicae, intima, media and adventitia. In the case of the thoracic aorta, the accumulation of calcium and phosphorus occurred primarily in the tunica media of aorta, secondarily in the tunica intima. With regard to the femoral artery, the accumulation of calcium and phosphorus occurred only in the tunica media, only in the tunica intima, or in both the tunicae media and intima. Therefore, the manner of accumulation of calcium and phosphorus in the femoral-arterial wall was different from that in the aortic wall. Comparing the upper and lower limb arteries, the calcium content was found to be higher in the femoral, popliteal, and dorsalis pedis arteries of the lower limb than that of the axillary and radial arteries of the upper limb.  相似文献   

18.
The distribution of adrenocorticotropin hormone/corticotropin-like intermediate lobe peptide was studied in the cat brain stem, using an indirect immunoperoxidase technique. No immunoreactive cell bodies were observed. However, a high density of immunoreactive fibers was found in the periaqueductal gray, the dorsal nucleus of the raphe, the locus coeruleus, and the marginal nucleus of the brachium conjunctivum. A moderate density was found in the central linear nucleus, the central tegmental field, the Kolliker-Fuse nucleus, the inferior central nucleus, and the postpyramidal nucleus of the raphe. A low density was found in the superior and inferior colliculi, the interpeduncular nucleus, the nucleus sagulum, the superior central nucleus, the cuneiform nucleus, the accessory dorsal tegmental nucleus, the nucleus of the solitary tract, the dorsal motor nucleus of the vagus, and the paralemniscal, magnocellular, gigantocellular, and lateral tegmental fields. Moreover, single immunoreactive fibers were observed in numerous nuclei of the cat brain stem. In comparison with previous studies carried out in the same region of the cat, as well as the rat and the human, our results point to a more widespread distribution of adrenocorticotropin hormone/corticotropin-like intermediate lobe peptide immunoreactive structures in the cat brain stem. This widespread distribution indicates that the peptide might be involved in several physiological functions of the cat brain stem.  相似文献   

19.
We studied the absorbing peripheral lymphatic vessel with the light microscope, the transmission electron microscope, the scanning electron microscope, and three-dimensional models of the diaphragm of several rodents and insectivores under normal and experimental conditions (lymphatic stasis and dehydration). To clarify the delicate and complex mechanism that permits drainage of the abdominal cavity contents into the lymphatic circulatory system, we introduced Polystyrene latex spherules, China ink, and Trypan blue into the abdominal cavities. After anatomical comparisons of the superficial and deep networks of absorbing peripheral lymphatic vessels at the tendinous and muscular portions of the diaphragm and after classification of lymphatic vessels into absorbing and conducting functions, we examined the stomata, which, owing to morphologic and topographic findings, we defined as stable structures. Furthermore, we observed that the stomata and submesothelial connective channel are fundamental elements that facilitate the flow of the corpuscular and liquid contents of the peritoneal cavity to the submesothelial absorbing lymphatic vessel wall. Also, we underlined that the genesis of the connective channel depends on the secondary cytoplasm extensions of two distinct adjacent endothelial cells, which, to facilitate the flow of the absorbed abdominal contents, completely coat this channel. Additionally, our observations illustrate that the secondary cytoplasm extensions do not engage in continuous relationships with the basal lamina of the mesothelium and with the margins of the stoma, and, hence, the hypothesis of "lymphatic stomata" as an expression of the anchoring of the borders of the open interendothelial junctions to the orifice margins of the stoma cannot be confirmed. Moreover, we describe the presence and formation of intraendothelial channels in the lymphatic endothelial wall. We affirm that this morphological entity is a dynamic unit, because its numerical density varies according to different physiological and experimental conditions to degrees of hydrostatic and colloidal osmotic pressure and, perhaps, also to the particular characteristics of the substances that the connective channel liberates into the endothelial wall of the lymphatic vessel. In conclusion, we affirm that the absorbing peripheral lymphatic vessels of the diaphragm, by way of intraendothelial channel formations, membrane diffusion, and the vesicular path of the endothelial cells, constitute the fundamental draining elements for the corpuscular and liquid contents of the abdominal cavity.  相似文献   

20.
为进一步提高武山铜矿综合回采效益,以胶结充填工艺推广使用为契机,在现有采矿工艺、技术装备条件下,积极摸索多中段同时采矿的方式,对多中段开采时留下的矿柱进行回收。针对多中段开采过程中存在的各种问题,通过管理创新攻关,改变回采顺序、优化胶结充填工艺、事先调节矿柱厚度、采取变更铲装设备、完善相关采准工程等多种管理和技术措施 ;并在建立完善考核体系、加大考核力度、制定相应的工艺管理制度的基础上,有效解决了由于多中段采矿造成的采场生产衔接困难等问题,同时也有效解决了多中段开采矿柱回收率偏低的问题,确保了安全生产,矿石回收率和采场生产能力得到了极大提高,经济效益和社会效益较为显著。  相似文献   

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