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81.
In recent decades, energy efficiency has been the priority for masonry buildings in order to keep up with ever more stringent requirements. For the evaluation of the sustainability of building solutions, however, the embodied energy to produce a building and finally to dispose of it at the end of its lifecycle are also important. The energy used for the disposal of a building and the processing of the residues are also important for the overall energy balance since the handling of natural resources is increasingly the centre point of thought and action. A research team at the Chair of Structural Design of TU Dresden has thus been working since 2012 on demountable solutions in masonry, which can be dismantled at the end of a building lifetime and sorted for recycling, which fully complies with the requirement for the reduction of rubbish and waste products. The high precision of block production today permits us to omit the levelling effect of mortar and to build dry buildings in the future, i.e. to do without the bonding principle. The associated strength reductions can be suffered without problems. The appropriate basics of such a dry building method have been researched in a collaboration between the ILEK in Stuttgart and the Xella Technologie‐ und Forschungsgesellschaft mbH in Emstal. In this research project with the abbreviation ”REMOMAB“, the basics of an energy‐efficient dry building method suitable for recycling were collected and made available for practical application. In a follow‐up project, these basics are being implemented and tested on an experimental building. Cost aspects are also to be taken into account and if possible, construction solutions available on the market will be used – modified if necessary. Another aim is for the first time to dismantle such a building and to rebuild it at another location. This is intended to demonstrate that a reuse is possible after dismantling and such a building method can react to changing demands in the housing market.  相似文献   
82.
Interconnected devices and intelligent applications have slashed human intervention in the Internet of Things (IoT), making it possible to accomplish tasks with less human interaction. However, it faces many problems, including lower capacity links, energy utilization, enhancement of resources and limited resources due to its openness, heterogeneity, limited resources and extensiveness. It is challenging to route packets in such a constrained environment. In an IoT network constrained by limited resources, minimal routing control overhead is required without packet loss. Such constrained environments can be improved through the optimal routing protocol. It is challenging to route packets in such a constrained environment. Thus, this work is motivated to present an efficient routing protocol for enhancing the lifetime of the IoT network. Lightweight On-demand Ad hoc Distance-vector Routing Protocol—Next Generation (LOADng) protocol is an extended version of the Ad Hoc On-Demand Distance Vector (AODV) protocol. Unlike AODV, LOADng is a lighter version that forbids the intermediate nodes on the route to send a route reply (RREP) for the route request (RREQ), which originated from the source. A resource-constrained IoT network demands minimal routing control overhead and faster packet delivery. So, in this paper, the parameters of the LOADng routing protocol are optimized using the black widow optimization (BWO) algorithm to reduce the control overhead and delay. Furthermore, the performance of the proposed model is analyzed with the default LOADng in terms of delay, delivery ratio and overhead. Obtained results show that the LOADng-BWO protocol outperforms the conventional LOADng protocol.  相似文献   
83.
Twelve patients suffering from an intractable duodenal ulcer are included in this review. Eleven were treated by superselective vagotomy without drainage, one had a selective vagotomy with pyloroplasty. A peroperative control of the gastric acidity after pentagastrin stimulation was used in all cases and permitted section of forgotten nerve fibers. Short-term results are satisfactory: after 2-6 months the clinical state of the patients is excellent (Visick I and II), basal acidity is decreased by 58 to 66% of preoperative value, the Hollander tests are negative except two. After more than 6 months, the few available results are satisfactory except one case of recurrent ulcer. The one case with a 1 year follow-up is excellent, clinically and as to acid secretion.  相似文献   
84.
A review of the International Conference on Crystal Lattice Defects which was held in Japan in September 1962.  相似文献   
85.
Gelation of alpha-lactalbumin (alpha-la) incubated with a protease from Bacillus licheniformis (BLP) at 50 degrees C for 4 h was monitored using small oscillatory shear and the large deformation properties of final gels were characterized by uniaxial compression. Transmission electron microscopy was used to visualize the microstructure. Gels made from alpha-la (10 g/l) using BLP were almost transparent, although somewhat whitish, and they were more than 20 times stiffer (measured as complex modulus) than equivalent gels made from beta-lactoglobulin (beta-lg) at the same concentration. The microstructure of the gels consisted of non-branching, apparently hollow strands with a uniform diameter close to 20 nm, similar in overall structure to microtubules. Adding Ca2+ in amounts of 50 or 100 mM changed the spatial distribution of the strands and resulted in a reduction in the failure stress recorded in uniaxial compression. Apart from affecting the microstructure, Ca2+ was shown to be essential for the formation of the gels. It is proposed. that the mechanism behind the self-assembly of the partially hydrolysed alpha-la into long tubes is a spatially restricted creation of ionic bonds between Ca2+ and carboxyl acid groups on peptide fragments resulting from the action of BLP on alpha-la. Proteolysis of alpha-la with BLP in the presence of Ca2+ thus results in formation of a strong gel with a microstructure not previously observed in food protein systems.  相似文献   
86.
研究了复原脱脂乳经不同加热处理后其酸奶凝胶形成过程中流变学特性的变化,复原脱脂乳经70~90℃处理10~25min,用D-葡萄糖-δ-内酯酸化成胶,用流变学方法动态监测凝胶性能。并监测酸化过程和成胶时间,结果显示,不同条件下自理后的脱脂乳在酸化过程中,pH值并未改变,但产储存模量(G′)和损失模量(G″)随受质变程度的增加而增加,只是当加热温度为90℃时反而随加热时间的延长而降低,在85℃加热25  相似文献   
87.
定量分析加热后乳清蛋白与酪蛋白的结合   总被引:3,自引:0,他引:3  
将复原脱脂乳在 70~ 90℃范围内加热 1 0~ 2 5min后 ,用超速离心分离出酪蛋白微粒 ,并用毛细管电泳法定量分析。结果显示 ,β-乳球蛋白更容易结合到酪蛋白微粒上。当加热条件为 70℃、1 0 min时就有相当多的 β-乳球蛋白发生了这种结合 ,这时酪蛋白微粒中没发现任何 α-乳清蛋白 ,只有当加热温度大于 75℃时才有少量 α-乳清蛋白与酪蛋白微粒结合。复原脱脂乳经 90℃、2 5min加热后几乎所有 β-乳球蛋白都已转入酪蛋白微粒部分 ,而只有近 50 %的α-乳清蛋白转入酪蛋白微粒。  相似文献   
88.
In current top‐down nanofabrication methodologies the design freedom is generally constrained to the two lateral dimensions, and is only limited by the resolution of the employed nanolithographic technique. However, nanostructure height, which relies on certain mask‐dependent material deposition or etching techniques, is usually uniform, and on‐chip variation of this parameter is difficult and generally limited to very simple patterns. Herein, a novel nanofabrication methodology is presented, which enables the generation of high aspect‐ratio nanostructure arrays with height gradients in arbitrary directions by a single and fast etching process. Based on metal‐assisted chemical etching using a catalytic gold layer perforated with nanoholes, it is demonstrated how nanostructure arrays with directional height gradients can be accurately tailored by: (i) the control of the mass transport through the nanohole array, (ii) the mechanical properties of the perforated metal layer, and (iii) the conductive coupling to the surrounding gold film to accelerate the local electrochemical etching process. The proposed technique, enabling 20‐fold on‐chip variation of nanostructure height in a spatial range of a few micrometers, offers a new tool for the creation of novel types of nano‐assemblies and metamaterials with interesting technological applications in fields such as nanophotonics, nanophononics, microfluidics or biomechanics.  相似文献   
89.
We present a simple and versatile approach for fabricating terahertz lenses based on compression molding of micropowder polymer materials in a tabletop hydraulic press. To demonstrate the feasibility of this approach, a biconvex lens shape is calculated using a ray-tracing algorithm and lenses based on two different micropowders are fabricated. As the powder materials have different refractive indices, the resulting lenses share the same geometric shape but differ in their respective focal length. The focusing properties of the lenses are evaluated by transversal and sagittal beam profile measurements in a fiber-coupled terahertz time-domain spectroscopy system, confirming the excellent imaging qualities of the compression molded lenses.  相似文献   
90.
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