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31.
OBJECTIVE: The purpose of this study was to analyze the importance of psychologic factors in patients with oral lichen planus, and attempts were made to identify possible personality features characteristic of patients with oral lichen planus. STUDY DESIGN: The study involved 100 patients with oral lichen planus (group 1) and 50 control subjects (group 2). We applied the following psychometric tests to both groups: Spielberger State-Trait Anxiety Inventory, Cattell Personality Questionnaire 16PF, Hassanyeh Rating of Anxiety-Depression-Vulnerability, Beck Depression Inventory, Raskin Depression Screen, and Covi Anxiety Screen. RESULTS: The patients with oral lichen planus were found to exhibit greater anxiety, as reflected by statistically significant scores with the anxiety tests that were used (Spielberger State-Trait Anxiety Inventory, Cattell Personality Questionnaire 16PF, Hassanyeh Rating of Anxiety-Depression-Vulnerability, and Covi Anxiety Screen). The patients with oral lichen planus likewise exhibited greater depression than the controls in all 3 depression tests applied (Beck Depression Inventory, Hassanyeh Rating of Anxiety-Depression-Vulnerability, and Raskin Depression Screen) and were more vulnerable to psychic disorders on the basis of the PD subscales (vulnerability) of the Hassanyeh questionnaire. Three features (conformity to the group, astuteness, and rebelliousness) defined the personalities of our patients with oral lichen planus, according to the Cattell 16PF questionnaire. Finally, those patients with erosive lichen planus exhibited higher depression scores than patients with nonerosive lichen planus. CONCLUSIONS: Despite the higher anxiety scores observed in patients with oral lichen planus, it was not established that the observed psychologic alterations constitute a direct etiologic factor of oral lichen planus; nor was it established that such alterations are a consequence of oral lichen planus and its lesions.  相似文献   
32.
Reusing software: issues and research directions   总被引:2,自引:0,他引:2  
Software productivity has been steadily increasing over the past 30 years, but not enough to close the gap between the demands placed on the software industry and what the state of the practice can deliver; nothing short of an order of magnitude increase in productivity will extricate the software industry from its perennial crisis. Several decades of intensive research in software engineering and artificial intelligence left few alternatives but software reuse as the (only) realistic approach to bring about the gains of productivity and quality that the software industry needs. In this paper, we discuss the implications of reuse on the production, with an emphasis on the technical challenges. Software reuse involves building software that is reusable by design and building with reusable software. Software reuse includes reusing both the products of previous software projects and the processes deployed to produce them, leading to a wide spectrum of reuse approaches, from the building blocks (reusing products) approach, on one hand, to the generative or reusable processor (reusing processes), on the other. We discuss the implication of such approaches on the organization, control, and method of software development and discuss proposed models for their economic analysis. Software reuse benefits from methodologies and tools to: (1) build more readily reusable software and (2) locate, evaluate, and tailor reusable software, the last being critical for the building blocks approach. Both sets of issues are discussed in this paper, with a focus on application generators and OO development for the first and a thorough discussion of retrieval techniques for software components, component composition (or bottom-up design), and transformational systems for the second. We conclude by highlighting areas that, in our opinion, are worthy of further investigation  相似文献   
33.
One of the most prominent hole-transporting material (HTM) for hybrid perovskite solar cells has been 2,2″,7,7″-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD), which is commonly doped with metal bis(trifluoromethylsulfonyl)imide (M(TFSI)n) salts that contribute to generating the active radical cation HTM species. The underlying role of the metal cation, however, remains elusive. Here, the effect of metal cations (M = Li, Zn, Ca, Cu, and Sc) on doping spiro-OMeTAD is analyzed by a combination of techniques, including electron paramagnetic resonance spectroscopy and cyclic voltammetry, which is complemented by photovoltaic device and hole mobility analysis. As a result, the authors reveal the superiority of Zn(TFSI)2 salts in device performances as compared to the others, including redox-active Cu(TFSI)2. This analysis thereby unravels new design principles for dopant engineering in HTMs for hybrid perovskite photovoltaics.  相似文献   
34.
This study was designed to investigate functionality of tetracycline-loaded chitosan-halloysite nanocomposite films, with focus on evaluating the influence of chitosan molar mass on films applicability for sustained local antibiotic delivery. The films were prepared by casting and solvent evaporation using low, medium, and high molar mass chitosan. SEM analysis revealed compact, nonporous and rough surface of the nanocomposite films due to the presence of halloysite agglomerates and tetracycline crystals. Increasing chitosan molar mass led to higher values of elongation at break (from 21.65 ± 2.65 to 34.48 ± 2.34%), tensile strength (from 134.8 ± 13.21 to 246.36 ± 14.69 MPa), and elastic modulus (from 633.79 ± 128.37 to 716.55 ± 60.76 MPa) of the nanocomposite films. FT-IR, XRPD, and thermal analyses confirmed molar mass dependent chitosan-halloysite interactions and improved thermal stability of the nanocomposite films in comparison with chitosan films. The nanocomposite films released tetracycline in a sustained manner, with the slowest release achieved from the films consisting of low molar mass chitosan. Chitosan molar mass was confirmed to be a functionality-related characteristic of chitosan-halloysite nanocomposite films as potential sustained-release carriers for topical delivery of antibiotics. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48406.  相似文献   
35.
This paper describes an investigation of the corrosion behavior of Cu37Zn brass in a solution of sodium tetraborate, at pH 10.0, with the addition of chloride ions and benzotriazole (BTA) inhibitor. The application of cyclic voltammetry has led to the conclusion that the anodic current densities increase with increase in immersion time in sodium tetraborate solution as well as in solutions of sodium tetraborate containing chloride ions of various concentrations. The values of anodic current density are considerably smaller in sodium tetraborate solutions with the addition of BTA compared with those in the inhibitor-free solution.The study also analyses the electrochemical behavior of Cu37Zn brass after various times of alloy exposure to BTA solution, as well as its behavior in BTA solutions of various concentrations. Also, the study describes the electrochemical behavior of Cu37Zn brass after the effect of Cl ions, but subsequent to the formation of a polymeric protective film on the electrode surface.  相似文献   
36.
Influence of inorganic anions on electrochemical behaviour of pyrite   总被引:1,自引:0,他引:1  
This work gives an investigation of pyrite behaviour during anodic oxidation in solutions of four inorganic acids: sulphuric, hydrochloric, phosphoric and perichloric acid. In wider range of concentrations, the influence of acids on following parameters was investigated: rate of establishment and corrosion potential value, Tafel's slope, corrosion current and electrodic reaction order. Based on potentiodynamic and chronoamperometric investigations, it was found out that pyrite oxidation is developed in three regions conditionally named active, passive and transpassive region. It was also found out that pyrite is intensively dissolved at potentials higher than 0.75 V versus SCE and that oxidation rate of pyrite is the highest in hydrochloric acid solutions (≥1 M HCl). By comparison of obtained results, it was concluded that there are no distinctive differences in pyrite behaviour during anodic oxidation in solutions of investigated acids.  相似文献   
37.
Addy  Edward  Mili  Ali  Yacoub  Sherif 《Software Quality Journal》1999,8(3):169-195
We report on a term project to conduct domain engineering followed by application engineering for a specific set of applications. We discuss some of the observations we have made on this project, as well some of the lessons we have learned.  相似文献   
38.
To determine whether the geometrical accuracy of small printed elements does not worsen on recycled paper, microscopic analysis of the dot area and the graphic elements raggedness printed on different types of recycled and coated papers at different screen ruling was carried out. Experimental tests have shown that geometrical accuracy of small elements printed on recycled paper/cardboard, in comparison to pictures printed on primary production paper is almost the same. Microsc. Res. Tech. 76:890–892, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
39.
Ljubica Djukanović  Biserka Aksić‐Miličević  Miodrag Antić  Jovan Baković  Željko Varga  Biljana Gojaković  Nada Dimković  Verica Ðorđević  Vidojko Ðorđević  Stevan Ðurić  Sunčica Ðurić  Nenad Zec  Rosa Jelačić  Zoran Kovačević  Tatjana Lazarević  Višnja Ležaić  Milan Mandić  Ivko Marić  Srboljub Milenković  Olivera Milićević  Milena Mišković  Igor Mitić  Zora Nikolić  Draga Pilipović  Stevo Plješa  Miroslava Radaković  Nenad Rakić  Vanja Rangelov  Radivoje Stojanović  Marina Stojanović‐Stanojević  Biserka Tirmenštajn‐Janković  Branimir Haviža‐Lilić  Edvin Hadžibulić  Rajko Hrvačević  Anica Cvetičanin 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(4):517-525
The study presents the epidemiological features of patients treated with renal replacement therapy (RRT) in Serbia from 1997 to 2009 and compares the results of hemodialysis treatment in 1999 and 2009. Epidemiological data were obtained from the National Registry of RRT patients and data on hemodialysis treatment from special surveys conducted in 1999 and 2009. Within the period 1997–2009 the incidence of patients on RRT increased from 108 to 179 per million population (pmp), prevalence rose from 435 to 699 pmp, while mortality rate fell from 20.7% to 16.7%. The frequency of patients with glomerulonephritis decreased, while that of patients with diabetes and hypertensive nephropathy increased. In late 2009 there were 5208 patients receiving RRT in Serbia. Within the examined period new hemodialysis and reverse osmosis equipment were purchased, high‐flux dialyzers with synthetic membranes were increasingly used and the number of patients receiving hemodiafiltration increased to 17.6%. Kt/V greater than 1.2 was recorded in 16% of the patients in 1999 but 52% in 2009. Options for correction of anemia and mineral disorders have also improved. The percentage of patients with HbsAg (13.8% vs. 4.8%) as well as anti‐hepatitis C virus antibodies positive patients (23.2% vs. 12.7%) was significantly lower in 2009 than in 1999. Both the incidence and prevalence of RRT patients in Serbia are rising continuously, while the mortality rate is falling. More favorable conditions for dialysis treatment have brought about significant improvement in the results over the last 10 years.  相似文献   
40.
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