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1.
BACKGROUND: X-linked severe combined immunodeficiency (SCIDXI) is an inherited immune defect which leads to death in infancy from severe infections. The defect is caused by mutations of the IL-2RG gene that encodes for the common gamma chain shared by several cytokine receptors. The disease is characterised by lack of T and NK cells with normal numbers of B cells. SCIDXI can be cured by bone marrow transplantation (BMT) or prevented by abortion after prenatal diagnosis. METHODS: A male fetus was diagnosed as having SCIDXI by molecular, immunophenotypic, and functional analyses. The fetus was injected intraperitoneally under ultrasound guidance with CD34 haematopoietic progenitor cells purified from paternal bone marrow and T-cell depleted by E rosetting. Chimerism analysis was by HLA-DQ alpha typing and gamma-chain staining on cord blood. FINDINGS: A healthy 3.6 kg boy was delivered by caesarean section at 38 weeks of gestation with no clinical or laboratory signs of graft-versus-host disease. Engraftment of donor-derived CD2 cells was found at birth. At 3.5 months of age the infant is well and his T-cell counts and function are normal. INTERPRETATION: In-utero transplantation of haematopoietic progenitor cells allowed immune reconstitution of a fetus with SCIDXI and may be an alternative to elective abortion. Our report should encourage applications of this method to other inherited disorders curable by BMT.  相似文献   
2.
A robotics wheelchair for crowded public environment   总被引:1,自引:0,他引:1  
Describes the robotic wheelchair MAid (Mobility Aid for Elderly and Disabled People). MAid's task is to support and transport people with limited motion skills. It is based on a commercial wheelchair that has been equipped with an intelligent control and navigation system. Conversations with disabled and elderly people and with their physicians indicate that the automatic functions desired in a robotic wheelchair do not include following walls or passing doorways, but do include navigation in narrow, cluttered environments and through wide, crowded areas. MAid performs these functions  相似文献   
3.
We modified synthetic isoprene rubber by means of the in situ generation of silica particles through the sol–gel process starting from tetraethoxysilane (TEOS) as an inorganic oxide precursor. Different reaction conditions were investigated with variations in the initial TEOS content, the reaction time of the sol–gel process, and the presence of a coupling/surfactant agent (octyltriethoxysilane). Organic–inorganic hybrid materials with a silica content up to 70 phr were obtained with the complete conversion of TEOS to silica for a long enough sol–gel reaction time. A very homogeneous dispersion of silica particles was observed in all cases together with a very good adhesion between the filler and matrix. The size of the in situ generated silica was controlled by the appropriate addition of octyltriethoxysilane. Swelling and extraction tests and dynamic mechanical analysis indicated that the vulcanization process of isoprene rubber was perturbed by the sol–gel process; this led to a slight decrease in the crosslinking degree. However, a significant reinforcing effect due to the presence of silica particles was observed for all of the investigated samples. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
4.
Poly(butylene terephthalate) nanocomposites with organically modified montmorillonites have been prepared by in‐situ ring opening polymerization of PBT cyclic oligomers. High molecular weight polymers can be obtained by choosing the proper polymerization conditions and catalyst in very short polymerization time (10 min) and low temperature (205°C). A better dispersion of the clay and a consistently higher Mw have been obtained by this method respect to the standard melt intercalation approach, leading to improved thermo‐mechanical properties of the nanocomposite. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
5.
Zeno 《艺术与设计》2009,(1):238-241
成为“Jumper(心灵传输者)”必定是每个人曾有过的梦想。没有关系,即使你不能倚靠心灵的力量而遍游世界,那些有趣的礼物同样能带来移动的快感。  相似文献   
6.
We show that it is possible to detect specifically adsorbed bacteriophage directly by breaking the interactions between proteins displayed on the phage coat and ligands immobilized on the surface of a quartz crystal microbalance (QCM). This is achieved through increasing the amplitude of oscillation of the QCM surface and sensitively detecting the acoustic emission produced when the bacteriophage detaches from the surface. There is no interference from nonspecifically adsorbed phage. The detection is quantitative over at least 5 orders of magnitude and is sensitive enough to detect as few as 20 phage. The method has potential as a sensitive and low-cost method for virus detection.  相似文献   
7.
Imidazolium poly(butylene terephthalate) ionomers with ionic groups located randomly along the polymer chain or selectively as end-groups (telechelic) have been prepared in order to determine their antimicrobial (AM) activity. Two different approaches have been followed for the linkage of the imidazolium to the polymer backbone: a covalent bond and an ionic aggregation to sulfonated groups covalently bonded to the polymer. The ionic groups have been linked to the polymer in order to improve the long-term AM activity since the low molecular weight additives commonly used tends to migrate toward the surface during use. We have found that imidazolium ionomers present AM activity comparable with that of commercial antimicrobial agents such as Triclosan. The AM activity depends on the polymer architecture, the telechelic approach being more active compared to the random approach. We have proved that imidazolium ionomers retain their high AM activity even after 6 days in water at 60 °C while Triclosan consistently loses his activity.  相似文献   
8.
Personal and Ubiquitous Computing - This article presents a study concerning the evaluation of a smart home control system for elderly people with a sample of 10 users in a city in the interior of...  相似文献   
9.
Following the continuous increase in computational power of consumer hardware, interactive virtual environments have been recently enriched with more and more complex deformable objects. However, many physics engines are still very limited in the way they handle interacting rigid and deformable objects. This paper proposes a constraint‐based approach to real‐time simulation of coupled rigid and deformable objects capable of providing two‐way interactions. Similar techniques have seen widespread usage for either rigid or deformable objects, but not for the simultaneous simulation of both. By extending such approaches, we show not only how interaction is possible but also how it can be performed at real‐time rates. We address contact response and also show how to implement typical constraints to enforce limitations in the degrees of freedom and to enhance the dynamical properties of deformable objects. The method is easily integrated into existing physics engines that use similar constraint solvers and is independent on the kind of deformable object paradigm chosen. The provided simulation results show that the method is fast and effective in handling contacts between rigid and deformable objects and in simulating friction and other kinds of constraints. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
10.
A 334g TeO2 crystal is operating since January '93 at Gran Sasso National Laboratories as a thermal detector to search for neutrinoless decay of130Te. The reduction of environmental radioactivity is accomplished by means of a 10 cm thick external lead shielding and a plexiglas box against222Rn, while an inner ultra-low activity lead shield of at least 3.5 cm in every direction suppresses the residual local radioactivity near the crystal. The good energy resolution and the peak-to-Compton efficiency of the detector allow to understand the main features of the residual background. In particular, we are able to reach a sensitivity in the internal contamination of238U and232Th of the crystal of the order of 10–13 g/g, better than that of modern mass spectroscopy methods. Pulse acquisition and analysis techniques are reported and discussed.Present limit on neutrinoless decay half-life time of130Te obtained with this detector is of the order of 1022y at 68% C.L., exceeding by one order of magnitude the value quoted by the inclusive geochemical measurements, which have therefore to be attributed mainly to the 2-neutrino channel.On leave from the Dept. of Physics, University of Zaragoza  相似文献   
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