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531.
In the course of the investigation of biocatalytic gas-liquid reactions with color change in straight and coiled capillaries, a non-invasive evaluation method is needed to determine reaction progress and selectivity. Correlations between hydrodynamics, mass transfer phenomena, and reaction kinetics are in the focus of our work. For this purpose, it is necessary to investigate the flow and evaluate the reaction progress without disturbing the flow. Digital image processing (DIP) is presented as a suitable optical evaluation method for reactions with color change in capillary reactor designs. The developed DIP program is independent from the capillary reactor design, applicable to differently colored systems, and can analyze up to three different species simultaneously.  相似文献   
532.
Progressive Familial Intrahepatic Cholestasis (PFIC) are inherited severe liver disorders presenting early in life, with high serum bile salt and bilirubin levels. Six types have been reported, two of these are caused by deficiency of an ABC transporter; ABCB11 (bile salt export pump) in type 2; ABCB4 (phosphatidylcholine floppase) in type 3. In addition, ABCB11 function is affected in 3 other types of PFIC. A lack of effective treatment makes a liver transplantation necessary in most patients. In view of long-term adverse effects, for instance due to life-long immune suppression needed to prevent organ rejection, gene therapy could be a preferable approach, as supported by proof of concept in animal models for PFIC3. This review discusses the feasibility of gene therapy as an alternative for liver transplantation for all forms of PFIC based on their pathological mechanism. Conclusion: Using presently available gene therapy vectors, major hurdles need to be overcome to make gene therapy for all types of PFIC a reality.  相似文献   
533.
This paper describes the studies of the mechanical characteristics of flexible MEMS components including theoretical approaches, finite element analysis and experimental investigations. Modeling and finite element analyses together with theoretical and experimental investigations are performed to estimate the elastic behavior of MEMS components as microcantilevers, microbridges and micromembranes. Finite element analysis of microcomponents deflections under different loading and the stress distribution in beams are determined and compared with the experimental measurements performed using an atomic force microscope. The modeling of a micromembrane supported by four hinges that enable out-of-plane motion is presented. Finite element analysis and experimental investigations are performed to visualize the deflection of the mobile part of the micromembrane under an applied force and the stress distribution in hinges. In additional, this paper provides analytical relations to compute the stiffness and the stress of the investigated flexible MEMS components.  相似文献   
534.
Today, the thermal disposal of waste is the acknowledged state of the art. During the incineration process various volume flows are generated, in particular carbon dioxide. This study describes a novel approach to the material use of carbon dioxide for methanol. The developed model enables a timely evaluation of investment and operating costs and generates a reliable basis for decision-making within the framework of a site analysis.  相似文献   
535.
In this work two potential new species for forest plantation projects in Northern Brazil were evaluated for their suitability in particleboard production. The main evaluated parameters of the laboratory boards were pH value and buffer capacity of the particles, compaction ratio, thickness swelling, modulus of elasticity (MOE), modulus of rupture (MOR) and internal bond (IB). The results showed that both species are highly suitable for particleboard production as they presented low densities (400–430 kg/m³), light color, good compressibility and no apparent adverse reactions after UF-resination.  相似文献   
536.
Genistein is one of the most studied phytocompound in the class of isoflavones, presenting a notable estrogenic activity and in vitro and/or in vivo benefits in different types of cancer such as those of the bladder, kidney, lung, pancreatic, skin and endometrial cancer. A big inconvenience for drug development is low water solubility, which can be solved by using hydrophilic cyclodextrins. The aim of this study is to theoretically analyze, based on the interaction energy, the possibility of a complex formation between genistein (Gen) and three different ramified cyclodextrins (CD), using a 1:1 molar ratio Gen:CD. Theoretical data were correlated with a screening of both in vitro and in vivo activity. Proliferation of different human cancer cell lines, antimicrobial activity and angiogenesis behavior was analyzed in order to see if complexation has a beneficial effect for any of the above mentioned activities and if so, which of the three CDs is the most suitable for the incorporation of genistein, and which may lead to future improved pharmaceutical formulations. Results showed antiproliferative activity with different IC50 values for all tested cell lines, remarkable antimicrobial activity on Bacillus subtilis and antiangiogenic activity as revealed by CAM assay. Differences regarding the intensity of the activity for pure and the three Gen complexes were noticed as explained in the text. The data represent a proof that the three CDs can be used for furtherer research towards practical use in the pharmaceutical and medical field.  相似文献   
537.
In chemical oxidative homopolymerization of aniline-N-propanesulfonic acid, ammonium persulfate has been used as an oxidant to obtain water-soluble and self-acid-doped polyanilines. Copolymerization of aniline-N-propanesulfonic acid with aniline, using three feed molar ratios of comonomers has been studied, as well. The polymers and copolymers had moderate molecular weights and were soluble in water and polar solvents. They have been obtained in self-acid-doped form, as has been evidenced by UV?CVis spectroscopy, as green-colored materials, and can be de-doped with alkaline solutions. The propanesulfonic groups had not cleaved during the oxidative polymerization and the atomic ratio between nitrogen and sulfur atoms (N/S) was determined by X-ray photoelectron spectroscopy which was consistent with the chemical structure. The chemical structures and morphologies of the homo- and copolymers have been studied by FTIR, 1HNMR, UV?CVis, thermogravimetric analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, and X-ray diffraction methods. The X-ray diffraction patterns of the homo- and copolymers have showed a high degree of crystallinity which can be explained by the ionic interaction between propanesulfonate anions and the amine nitrogen atoms of the main chain, resulting in the layering structure of the polyaniline chains. Electrical conductivity of the homopolymer determined at room temperature on pressed pellet was 0.0038?S/cm, while the copolymers show higher conductivities compared with homopolymer.  相似文献   
538.
This paper provides the first comprehensive evaluation and analysis of modern (deep-learning-based) unsupervised anomaly detection methods for chemical process data. We focus on the Tennessee Eastman process dataset, a standard litmus test to benchmark anomaly detection methods for nearly three decades. Our extensive study will facilitate choosing appropriate anomaly detection methods in industrial applications. From the benchmark, we conclude that reconstruction-based methods are the methods of choice, followed by generative and forecasting-based methods.  相似文献   
539.
540.
The structural properties of some tellurite glasses were investigated by FT-IR spectroscopy, density measurements, and quantum chemical calculations. Main results reveal that the ratio TeO4/TeO3 is found to decrease in the order V2O5 > B2O3 > P2O5. For borate–tellurate glasses, the Van Hove singularities corresponding to Te 5s orbital-derived states are cleft suggesting that there are strong tellurium–oxygen interactions. On the other hand, a strong effect of TeO2 on the vitreous B2O3 network is also demonstrated by FT-IR spectrum. This effect yields the apparition of small peaks in the region ranges between 800 and 1600 cm−1 and probably the partial crystallization of the sample. Its spectral features are due to the B–O bond stretching of [BO4] and [BO3] structural units. The quantum chemical data obtained by us show that phosphate–tellurite and vanado–tellurate glasses can behave as semiconductors, whereas borate–tellurite glasses as insulators because the gap between the valence and conduction bands is >3 eV.  相似文献   
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