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41.
In the creation of ERP systems, it is important to plan the pilot testing. In pilot projects (also known as experimental projects), the main functions of the system are tested by a limited set of advanced users. In planning the pilot testing, the key is to determine its extent. With too little testing, fundamental functions of the system may not be checked, and the probability of detecting significant errors only at complete rollout will be high. With excessive testing, the work required in the pilot project will be considerably increased, and the required speed and flexibility will not be attained in testing the basic functions. The effectiveness of pilot testing will be no better than the effectiveness of full-scale introduction. A mathematical formulation of the determination of the optimal extent of pilot testing is developed on the basis of the generation of a portfolio of IT services and their scheduling in the creation of the ERP system for a large steel company. The solution of this problem takes the form of a set of services that must be verified and the relations between them, within the specified constraint on the resources devoted to testing, such that optimal results are obtained. The solution is obtained by network programming, based on a structurally similar network representation of the relevant criteria and constraints. A solution procedure is outlined, along with an example of its use. In this procedure, dichotomous programming is used to solve individual problems. The approximate solutions obtained may be improved by solving a double network-programming problem. The branch and bound method may be used to find the global optimum of the initial problem. In that approach, the boundaries are values of the target functions for the approximate solutions. Generalization of this problem is based on the preferences of IT-service users regarding the quality of verification of different relations between the services. Those preferences may be taken into account by weighting the corresponding relationships. That leaves the basic solution procedure unchanged. 相似文献
42.
英落菱镁矿选矿试验研究 总被引:1,自引:0,他引:1
针对菱镁矿矿石中脉石杂质的赋存特点,采用常规反正浮流程,使用Na2CO3反浮矿浆调浆,六偏磷酸钠加水玻璃抑制白云石和硅酸盐脉石杂质,并结合浮选前脱泥的工艺,达到了镁钙硅有效分离的目的,较常规工艺提高了浮选精矿指标。 相似文献
43.
挑选120名不同体型的青年男子,在静态下试穿12件运用相同款式与材料,不同筒径、组织结构和编织方法织造的无缝内衣,测试上体不同部位产生的服装压,同时要求被测试者进行主观压力舒适性评价。运用模糊数学、箱控图等统计方法对主客观实验数据进行分析,总结出无缝上衣服装压的分布规律及男式上体部位的舒适压范围:青年男子穿着无缝内衣,对肘部、侧缝部、臂干部和背部客观压力大小的变化非常敏感;前臂部、上臂部尽管客观压力大,但主观评价舒适,反之胸部客观压力小。主观评价差产生的原因是不同部位承受服装压的能力不同。提出男式无缝上衣设计中应尽量减小臂干部、背部、胸部服装压力。 相似文献
44.
45.
马钢高浓度OG泥喷浆工业性试验 总被引:3,自引:0,他引:3
本系统采用OG泥管道输送和高浓度喷浆(含固浓度35%~45%)至烧结的工艺。试验表明,该系统能实现OG泥全天候高浓度输送;马钢技术中心自主研制的动力喷洒头能满足烧结均匀喷洒的要求;在烧结混合料中喷洒OG泥既实现了固废资源的有效利用,又提高了烧结利用系数并降低了固体燃耗,社会效益及经济效益显著。 相似文献
46.
介绍了人工振动法增油技术在大庆油田的应用情况,并对现场试验的基础上数据进行了分析,研究,结果表明:大功率的地震震源所产生的弹性波场连续不断地作用于储层,可以提高原同的产出量,原油增产幅度一般为38.5%。该方法对于高含水,低渗透油田效果比较明显。 相似文献
47.
48.
The crystal structure of recombinant wild-type green fluorescent protein (GFP) has been solved to a resolution of 1.9 A by multiwavelength anomalous dispersion phasing methods. The protein is in the shape of a cylinder, comprising 11 strands of beta-sheet with an alpha-helix inside and short helical segments on the ends of the cylinder. This motif, with beta-structure on the outside and alpha-helix on the inside, represents a new protein fold, which we have named the beta-can. Two protomers pack closely together to form a dimer in the crystal. The fluorophores are protected inside the cylinders, and their structures are consistent with the formation of aromatic systems made up of Tyr66 with reduction of its C alpha-C beta bond coupled with cyclization of the neighboring glycine and serine residues. The environment inside the cylinder explains the effects of many existing mutants of GFP and suggests specific side chains that could be modified to change the spectral properties of GFP. Furthermore, the identification of the dimer contacts may allow mutagenic control of the state of assembly of the protein. 相似文献
49.
MJ Clemons E Marshall J Dürig K Watanabe A Howell D Miles H Earl J Kiernan A Griffiths K Towlson P DeTakats NG Testa M Dougal MG Hunter LM Wood LG Czaplewski A Millar TM Dexter BI Lord 《Canadian Metallurgical Quarterly》1998,92(5):1532-1540
BB-10010 is a variant of the human form of macrophage inflammatory protein-1alpha (MIP-1alpha), which has been shown in mice to block the entry of hematopoietic stem cells into S-phase and to increase their self-renewal capacity during recovery from cytotoxic damage. Its use may constitute a novel approach for protecting the quality of the stem cell population and its capacity to regenerate after periods of cytotoxic treatment. Thirty patients with locally advanced or metastatic breast cancer were entered into the first randomized, parallel group controlled phase II study. This was designed to evaluate the potential myeloprotective effects of a 7-day regimen of BB-10010 administered to patients receiving six cycles of 5-fluorouracil (5-FU), adriamycin, and cyclophosphamide (FAC) chemotherapy. Patients were randomized, 10 receiving 100 microgram/kg BB-10010, 11 receiving 30 microgram/kg BB-10010, and nine control patients receiving no BB-10010. BB-10010 was well-tolerated in all patients with no severe adverse events related to the drug. Episodes of febrile neutropenia complicated only 4% of the treatment cycles and there was no difference in incidence between the treated and nontreated groups. Studies to assess the generation of progenitor cells in long-term bone marrow cultures were performed immediately preceding chemotherapy and at the end of six dosing cycles in 18 patients. Circulating neutrophils, platelets, CD 34(+) cells, and granulocyte/macrophage colony-forming cell (GM-CFC) levels were determined at serial time points in cycles 1, 3, and 6. The results showed similar hemoglobin and platelet kinetics in all three groups. On completion of the six treatment cycles, the average pretreatment neutrophil levels were reduced from 5.3 to 1.7 x 10(9)/L in the control patients and from 4.3 to 1.9 and 4.5 to 2.5 x 10(9)/L in the 30/100 microgram/kg BB-10010 groups, respectively. Relative to their pretreatment values, 50% of the patients receiving BB-10010 completed the treatment with neutrophil values significantly higher than any of the controls (P = .02). Mobilization of GM-CFC was enhanced by BB-10010 with an additional fivefold increase over that generated by chemotherapy alone, giving a maximal 25-fold increase over pretreatment values. Bone marrow progenitor assays before and after this standard regimen of chemotherapy indicated little long-term cumulative impairment to recovery from chemotherapy. Despite the limited cumulative damage to the bone marrow, which may have minimized the protective value of BB-10010 during this regimen of chemotherapy, better recovery of neutrophils in the later treatment cycles with BB-10010 was indicated in a number of patients. 相似文献
50.
Interviews of a representative sample of 201 physicians (general practitioners, gynecologists, pediatricians) with a mean age of 47 years show: there is a unmanageable amount of information about drugs and their risks. The physicians prefer practical experience rather than specialized literature. As a result they plead for a central authority of information with periodical reports on the current knowledge of drug-therapy and with the possibility of therapeutical consultation. 相似文献