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排序方式: 共有1594条查询结果,搜索用时 31 毫秒
961.
Julia Wagner Mark Gruber Alexander Hinderhofer Andreas Wilke Benjamin Bröker Johannes Frisch Patrick Amsalem Antje Vollmer Andreas Opitz Norbert Koch Frank Schreiber Wolfgang Brütting 《Advanced functional materials》2010,20(24):4295-4303
Small‐molecule photovoltaic cells using diindenoperylene (DIP) as a new donor material in combination with the fullerene C60 as an electron acceptor are demonstrated. In addition to the successful application in planar and bulk heterojunction devices, a comprehensive analysis including structural studies, the determination of the energy level alignment and electrical transport investigations is given, stressing the correlation between growth conditions, film morphology, and device performance. Due to pronounced crystallinity and a large surface area of DIP films grown at elevated temperature, exceptionally high fill factors of almost 75% are achieved in planar heterojunction cells. Bulk heterojunctions exhibit large‐scale phase separation forming a bicontinuous network of both molecular species, which enables efficient exciton dissociation and charge carrier transport. The high ionization potential of DIP and the favorable energy level alignment with the fullerene C60 yield large open circuit voltages close to 1 V and comparable power conversion efficiencies of about 4% in both cell architectures. 相似文献
962.
Faserbewehrter Beton wird heute zunehmend auch bei Tunnelbauwerken (Tunnelinnenschalen, Tübbinge) eingesetzt. Wesentliche Vorteile sind das hohe Tragvermögen, das daraus entstehende Einsparungspotential an herkömmlicher stabförmiger Bewehrung (Biegebewehrung, Bügelbewehrung in der Randzone), die Aufnahme von Spaltzugbeanspruchungen durch die Fasern, Rissbreitenbegrenzung, erhöhte Dauerhaftigkeit, verbesserter Brandwiderstand (insbesondere bei Verwendung von Kunststofffasern), Optimierung der Arbeitsabläufe etc. Neue Entwicklungen in der Betontechnologie haben in den letzten Jahrzehnten den faserbewehrten ultrahochfesten Beton (engl. UHPFRC – Ultra High Performance Fibre Reinforced Concrete) hervorgebracht. Im Rahmen dieser Arbeit wird der Einsatz des ultrahochfesten, stahlfaserbewehrten Betons beim zweischaligen Tübbingausbau untersucht. Als Referenzobjekt dient die derzeit im Bau befindliche Tunnelkette Perschling, die im Zuge des viergleisigen Ausbaus der Westbahnstrecke der Österreichischen Bundesbahnen (ÖBB) in Niederösterreich errichtet wird. Ziel der statischen Untersuchung ist es, unter der Randbedingung, dass die maximalen Verformungen des C 40/50‐Normalbetontübbings gemäß Ausschreibungsstatik nicht überschritten werden, herauszufinden, inwieweit die Schalendicke durch Einsatz einer alternativen UHPFRC‐Tübbingschale reduziert und dadurch wirtschaftliche Vorteile generiert werden können. Investigations on the application of Ultra‐High‐Performance‐Fibre‐Reinforced‐Concrete (UHPFRC) tunnel segments at the double shell lining construction. Today fibre reinforced concrete is increasingly applied for tunnel construction (tunnel linings, tunnel segments). The essential benefits are e.g. the higher load bearing capacity, savings potential on the conventional bending and binder reinforcement, the absorption of splitting forces by the fibres, crack width limitation, higher durability, improved fire resistance, optimization of the workflow, etc. Beside the steel fibres carbon or glass fibres and polypropylene fibres are being added increasingly. Recent developments in concrete technology have produced the Ultra‐High‐Performance Fibre‐Reinforced‐Concrete. This work examines the use of UHPFRC at the double shell segmental lining system. As reference object serves the currently constructed tunnel chain Perschling which is part of the four track west railway route extension in Lower Austria. The aim of the analysis is the design of an alternative UHPFRC shell with minimum thickness while maintaining the constraint that the deformations are not exceeding those in the tender design with its C 40/50 reinforced concrete segments. 相似文献
963.
Giesen C Mairinger T Khoury L Waentig L Jakubowski N Panne U 《Analytical chemistry》2011,83(21):8177-8183
We optimized multiplexed immunohistochemistry (IHC) on breast cancer tissue. Up to 20 tumor markers are routinely evaluated for one patient, and thus, a common analysis results in a series of time consuming staining procedures. As an alternative, we used lanthanides for labeling of primary antibodies, which are applied in IHC. Laser ablation (LA) ICPMS was elaborated as a detection tool for multiplexed IHC of tissue sections. In this study, we optimized sample preparation steps and LA ICPMS parameters to achieve a sufficient signal-to-background ratio. The results prove the high selectivity of applied antibodies, which was sustained after labeling. Up to three tumor markers (Her 2, CK 7, and MUC 1) were detected simultaneously in a single multiplex analysis of a 5 μm thin breast cancer tissue at a laser spot size of 200 μm. Furthermore, the LA ICPMS results indicate a significantly higher expression level of MUC 1 compared to Her 2 and CK 7, which was not obvious from the conventionally stained tissue sections. 相似文献
964.
Centrifugal forces are generated by a spinning impeller, of magnitudes that create large stresses. Aerodynamic forces are also imparted on an impeller blade, which varies with time and position. These two forces play different roles during compressor events. Damage accumulated from these events results in the fatigue failure of impeller material and structure. Therefore, it is important to design an impeller against dynamic and fatigue failure. The finite element method has been used in the study of impeller fracture mechanics and is regarded as an important tool in the design and analysis of material and structures. 相似文献
965.
Moríñigo José A. García-Muller Pablo Rubio-Montero Antonio J. Gómez-Iglesias Antonio Meyer Norbert Mayo-García Rafael 《The Journal of supercomputing》2020,76(9):6834-6859
The Journal of Supercomputing - This work summarizes the results of a set of executions completed on three fat-tree network supercomputers: Stampede at TACC (USA), Helios at IFERC (Japan) and Eagle... 相似文献
966.
Christoph Fleischer‐Trebes Nicolai Krasberg Christian Bramsiepe Norbert Kockmann 《化学,工程师,技术》2017,89(6):785-799
Modularly built production plants are considered for planning new chemical plants, in case they shall be designed quickly and transformable, flexible plants are required. To date, these plants are planned mostly by the conventional planning process, so that time saving is not achieved. This paper presents a module based planning approach, which allows a structured planning of new modular plants in a time‐efficient way. All required documents for building modules are stored in the Process Equipment Design documentation, which is available for re‐use in future projects. 相似文献
967.
Producing compliant business behaviour: disclosure of food inspection results in Denmark and Germany
Miroslava Bavorová Norbert Hirschauer 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(1):45-53
Public disclosure of food inspection results (??name-and-shame??) is increasingly used to promote compliance with food regulations. Name-and-shame measures tackle the problem of market failure by increasing transparency, strengthening the sovereignty of consumers and enabling them to make informed choices. Consumers prefer to buy from compliant food businesses. If information on compliance is successfully conveyed to consumers, non-compliant businesses will face a competitive disadvantage. They will be sanctioned not only by the state but also by a loss of market share. Additionally, social sanctioning from ??relevant others??, such as friends and regular customers, may be linked with market sanctions. Both economic and social sanctions further the motivation to comply. Name-and-shame measures are thereby expected to effectively increase compliance with food regulations while keeping costs low for tax payers. Regulatory strategies which are both effective and cost-efficient are said to be ??smart??. A prerequisite of smart regulatory approaches is that they are legally viable within a nation??s legal and constitutional environment. Against this background, and with a view to the current political discussions regarding the introduction of a public disclosure system in Germany, we carry out a comparative analysis of the well-established Danish smiley scheme and three pilot projects in Germany. Aiming at identifying the potential for improvement, we address the institutional design of these systems as well as their effectiveness and costs. 相似文献
968.
We demonstrate the reversible rod-to-sphere shape transition of gold/mesoporous silica core/shell nanorods, where the shell acts as an elastic nanocontainer during the shape change. It is shown, that elongated core/shell nanorods are transformed into spherical core/shell particles at 300 °C. The anisometric shape of the composite particles can be recovered upon in-situ seeded growth of the gold core. The mesoporous silica shell acts as a nanoscale confinement, enabling control over the growth procedure during the chemical reaction. The shell of the particles was found to be elastic; it shows conformal shape-change with the core material during the heating and the subsequent seeded growth process. The effect of the reaction conditions during the seeded growth on the resulting particle morphology was also investigated. It is demonstrated, that depending on the growth conditions, core/shell nanorods or larger core/shell nanospheres can be obtained. The shape transformation cycle can be repeated for the same system several times, where the break-up of the confining shell represents the physical limit of the process. 相似文献
969.
Ricardo Henrique BUZOLIN Marta MOHEDANO Chamini Lakshi MENDIS Beatriz MINGO Domonkos TOLNAI Carsten BLAWERT Karl Ulrich KAINER Haroldo PINTO Norbert HORT 《中国有色金属学会会刊》2018,(3)
研究了铸造ZK40、添加2%(质量分数)CaO和添加1%(质量分数)Y的ZK40镁合金的微观组织,并表征了金属间化合物相的形貌和分布。利用ZK40晶界处分散的金属间化合物颗粒,将添加了CaO或Y的ZK40的微观组织调整为沿晶界分布的金属间化合物的半连续网络结构。微观组织中没有检测到CaO,Ca存在于铸造过程中形成的金属间化合物Ca_2Mg_6Zn_3中。析氢和电化学交流阻抗谱分析显示,添加CaO后合金的耐腐性略有提高,而添加Y却对ZK40的耐腐蚀性有负面影响。浸泡试验结果显示,严重的局部腐蚀和沿金属间化合物的腐蚀对ZK40-Y合金的腐蚀过程有重要影响,而ZK40和ZK40-CaO合金的局部腐蚀不明显。ZK40合金中α-Mg基体中的显微偏析明显高于加CaO或Y的ZK40合金,这种作用结合合金表面形成了更加稳定的耐腐蚀层是ZK40-CaO合金的耐腐蚀性能提高的主要原因。 相似文献
970.