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51.
应用微反应装置研究了铑含量对Pt-Rh-Pd/Al2O3催化剂的催化活性以及吸附性能的影响.结果表明Rh含量在0%~0.015%之间时,催化剂对CO的活性曲线呈波浪形,对NO的活性曲线为增函数;当Rh含量超过0.015%时,增加Rh的量对CO和NO的转化率几乎无影响.在无助的情况下,用Al2O3为载体制作的Pt-Rh-Pd/Al2O3催化剂,其Pt、Rh、Pd之间的最佳比例为15320.Rh含量的增加有利于氧化性气体的吸附,不利于还原性气体的吸附.  相似文献   
52.
目的研制预防人乳头瘤病毒(HPV)感染的重组修饰的Ankara痘病毒(MVA)活载体疫苗。方法将HPV16L1基因插入MVA病毒转移载体psc11M2的P7·5启动子的下游,构建转移质粒psc11M2-L1,与MVA共转染鸡胚成纤维细胞(CEF),进行同源重组。通过9轮蓝斑筛选,以PCR和Westernblot鉴定重组病毒。结果获得的含目的片段的重组MVA病毒,表达产物与鼠抗人HPV16L1抗体发生阳性反应,目的蛋白相对分子质量约为55000。结论已成功地构建了可正确表达HPV16L1基因的重组MVA病毒株。  相似文献   
53.
目的 研究重组人成骨蛋白 -1(rhOP -1)在大肠杆菌中的克隆和非诱导表达。方法 利用RT -PCR技术 ,从正常胎儿肾组织总cDNA中扩增得到rhOP- 1成熟肽基因片段 ,再将rhOP- 1成熟肽基因克隆于原核融合表达载体pGEX- 4T- 2中 ,构建表达质粒pCCBC- OP- 1,并转化到大肠杆菌JM10 9(DE3)中 ,在发酵过程中不添加任何诱导剂。表达产物经SDS -PAGE分析。结果 扩增的目的基因序列与文献报道一致。表达的目的蛋白相对分子质量为 14 0 0 0 ,表达量达到菌体蛋白的 4 0 %。结论 克隆了人OP -1成熟肽基因 ,并实现了rhOP- 1的非诱导高效表达。  相似文献   
54.
This paper considers human server systems of queues that arise within the information technology services industry. We develop a two-phase stochastic optimization solution approach to effectively and efficiently address the capacity management and planning processes of information technology services delivery centers. A large collection of numerical experiments of real-world human server system environments investigates various issues of both theoretical and practical interest, quantifying the significant benefits of our approach as well as evaluating the financial-performance trade-offs often encountered in practice.  相似文献   
55.
目的 建立纤溶酶原饼环区 5 (Humanplasminogenkringle 5 ,hPK 5 )蛋白重组大肠杆菌高效表达体系 ,为高密度发酵创造条件。方法 观察一级、二级种子的生长状态 ,比较表达hPK 5蛋白的 4种重组工程菌株在相同条件下的表达情况 ,选出首选发酵种子 ;对其培养时间、诱导时间、培养基种类、pH等条件进行优化 ;并用凝胶成像分析系统对SDS PAGE结果进行分析。结果 经过筛选 ,JM10 9 pBV2 2 0 hPK 5 (简称JP5 )是获取hPK 5蛋白的首选工程菌株 ,其最佳表达条件是LB培养基 (pH 7.4、溶解氧充足 )、30℃培养 3h、4 2℃诱导 6h。在此条件下 ,JP5表达目的蛋白占菌体总蛋白的 38%左右。结论 为高密度发酵获取hPK 5蛋白奠定了实验基础  相似文献   
56.
A novel vibrotactile musical input device called the Vibrochord, which is designed to deliver patterns of vibration to the skin, not to the ear, through the use of a vibrotactile display called the Emoti-Chair, is evaluated using proposed evaluation frameworks. Findings show that the mixture of frameworks used in this study provided valuable insight into the design of this novel musical device. Results obtained through the implementation of a mixture of these frameworks show that the Vibrochord facilitated an increased accuracy rate over the traditional piano keyboard, when inexperienced vibrotactile musicians tried to repeat vibrotactile patterns or “melodies”.  相似文献   
57.
This paper investigates how social distance can serve as a lens through which we can understand human–robot relationships and develop guidelines for robot design. In two studies, we examine the effects of distance based on physical proximity (proxemic distance), organizational status (power distance), and task structure (task distance) on people׳s experiences with and perceptions of a humanlike robot. In Study 1, participants (n=32) played a card-matching game with a humanlike robot. We manipulated the power distance (supervisor vs. subordinate) and proxemic distance (close vs. distant) between participants and the robot. Participants who interacted with the supervisor robot reported a more positive user experience when the robot was close than when the robot was distant, while interactions with the subordinate robot resulted in a more positive experience when the robot was distant than when the robot was close. In Study 2, participants (n=32) played the game in two different task distances (cooperation vs. competition) and proxemic distances (close vs. distant). Participants who cooperated with the robot reported a more positive experience when the robot was distant than when it was close. In contrast, competing with the robot resulted in a more positive experience when it was close than when the robot was distant. The findings from the two studies highlight the importance of consistency between the status and proxemic behaviors of the robot and of task interdependency in fostering cooperation between the robot and its users. This work also demonstrates how social distance may guide efforts toward a better understanding of human–robot interaction and the development of effective design guidelines.  相似文献   
58.
The purpose of this study was first to extract the anthropometric data of typical Korean male adults, based on the three‐dimensional anthropometric data measured through the Size Korea project. The data were then analyzed to identify the differences in the anthropometric characteristics between typical Koreans and 3D Korean mannequinmannequins generated by digital human models. Revision equations were then suggested to improve the inaccuracy of digital human models. Typical Korean adults subject to the 3D body scan data were selected by factor analysis with respect to the 5th, 50th, and 95th percentiles. Comparisons of anthropometric differences included the differences of the height and length variables in the vertical direction and the breadth, depth, and circumference variables in the horizontal direction. These comparisons demonstrated the differences in the anthropometric characteristics between typical Koreans and Korean mannequins based on differences in body shape and proportions between Korean and Western populations. Typical Koreans have shorter legs and longer torso than those of such mannequins generated from their own modeling algorithms, and the body shape of Koreans is more of an inverted triangular shape compared to the models. Although 3D digital human models are required to be modified to appropriately reflect the Asian body shape, modification of the modeling algoritms is not available to the public. The revision equations that convert the Korean modeling data of RAMSIS and Human in CATIA into typical Korean anthropometric data were instead suggested by regression analysis. It is expected that the proposed revision equations will help the designer evaluate design alternatives and improve the suitability of ergonomic evaluation for Korean customers. © 2012 Wiley Periodicals, Inc.  相似文献   
59.
Fitts法则是人机交互领域预测人机工效的一个有效模型,在许多交互方式中都得到了验证,是传统人机工效研究的理论基础。然而在视线交互中,由于眼动肌肉神经控制机制与肢体运动不同,Fitts法则并不适用。近两年的相关研究提出了一个新的专门针对视线点击任务的难度指数IDeye,它比经典的Fitts指数更能准确预测视线交互的工效。然而,在新模型的有效性验证实验中并没有考虑两种典型的扫视运动(向心和离心运动)的差异。为此,在前期研究的基础上设计组织实验,验证了视线交互中离心和向心这两种眼球运动所带来的人机工效和稳定性的差异,并证实新的IDeye模型仍然能有效预测单纯的离心或向心扫视条件下的人机工效,是对视线交互工效研究的重要补充。  相似文献   
60.
A series of novel copolymers, poly(methacryloyl‐2‐oxy‐1,2,3‐propanetricarboxylic acid‐coexo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalic acid) [poly(MTCA‐co‐ETAc)], poly(methacryloyl‐2‐oxy‐1,2,3‐propanetricarboxylic acid‐co‐hydrogenethyl‐exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalate) [poly(MTCA‐co‐HEET)], and poly(methacryloyl‐2‐oxy‐1,2,3‐propanetricarboxylic acid‐co‐α‐ethoxy‐exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthaloyl‐5‐fluorouracil) [poly(MTCA‐co‐EETFU)], were prepared from corresponding monomers by photopolymerizations at 25°C for 48 h. The polymers were identified by FTIR, 1H‐NMR, and 13C‐NMR spectroscopies. The number‐average molecular weights of the fractionated polymers determined by GPC were in the range from 9400 to 14,900 and polydispersity indices were 1.2–1.4. The in vitro IC50 values of polymers against mouse mammary carcinoma (FM3A), mouse leukemia (P388), and human histiocytic lymphoma (U937) as cancer cell lines and mouse liver cells (AC2F) as a normal cell line were much higher compared to that of 5‐fluorouracil (5‐FU). The in vivo antitumor activities of monomers and polymers against mice bearing sarcoma 180 tumor cell line were better than those of 5‐FU. The inhibition of DNA replication and antiangiogenesis activities of MTCA and copolymers were better compared to those of 5‐FU. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 57–64, 2004  相似文献   
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