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11.
Poly(vinyl alcohol) has been functionalized with aldehydes in tetrahydrofuran (THF) with a good control of the grafting. A wide library of poly(vinyl acetals) could be obtained in order to study some structure/property correlations. The influence of the aldehyde nature on the functionalization rates has been studied, in particular for optical properties by measurement of the shininess for further applications in the cosmetic field. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40677.  相似文献   
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The present study proposes a new approach for the assessment of the human balance control. This approach is based on the decomposition of the center of pressure displacement using empirical mode decomposition (EMD) that provides an effective time-frequency analysis of non-stationary signals. Twenty-eight healthy subjects performed quiet standing in four conditions—feet apart/together with respect to eyes open/closed—while recording the stabilometric signals in the anteroposterior (AP) and mediolateral (ML) directions. The EMD method decomposes each stabilometric signal into several subsignals called intrinsic mode functions (IMFs). Stabilogram-diffusion analysis technique is applied to generate the diffusion curve of each IMF signal. Each diffusion curve is modeled as a second-order system and provides representative features, such as the gain parameter. Analysis of the gain parameter shows the major effect of visual input and feet conditions on the strategy to control/stabilize the balance. Significant differences were found between young and elderly, and between women and men. In addition, the impact of feet position seems to be higher in ML direction than in AP direction.  相似文献   
13.
Original basic or acidic organic compounds derived from guanidine or phenyl phosphonic acid were specifically designed and tested as new catalysts for the bulk synthesis of polyurethane prepolymers from a precursor system with particularly low reactivity (secondary alcohol + aliphatic isocyanate at low temperature). Both families showed interesting catalytic activities at 60–80 °C, but must nevertheless be used in much higher amounts (1 mol%, i.e. between 0.15 and 0.50 wt%) than traditional metal-based catalysts. The efficiency of guanidine derivatives seems to be related to their nucleophilicity, whereas that of phosphonic acid derivatives depends on their acidity. However, the solubility of the considered species in the reactive medium also plays a major role. The water/alcohol selectivity of the catalysts, especially at room temperature, was then examined as an additional criterion. Guanidines are not selective and favor the reaction of isocyanate groups with water as much as that with alcohols. Phenyl phosphonic acid derivatives are more selective, and particularly pentafluorophenyl phosphonic acid displays a remarkable catalytic activity together with an acceptable selectivity and could represent an interesting and safer alternative to toxic tin and mercury derivatives for many industrial polyurethanes.  相似文献   
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Mitochondrial dysfunctions are implicated in several pathologies, such as metabolic, cardiovascular, respiratory, and neurological diseases, as well as in cancer and aging. These metabolic alterations are usually assessed in human or murine samples by mitochondrial respiratory chain enzymatic assays, by measuring the oxygen consumption of intact mitochondria isolated from tissues, or from cells obtained after physical or enzymatic disruption of the tissues. However, these methodologies do not maintain tissue multicellular organization and cell-cell interactions, known to influence mitochondrial metabolism. Here, we develop an optimal model to measure mitochondrial oxygen consumption in heart and lung tissue samples using the XF24 Extracellular Flux Analyzer (Seahorse) and discuss the advantages and limitations of this technological approach. Our results demonstrate that tissue organization, as well as mitochondrial ultrastructure and respiratory function, are preserved in heart and lung tissues freshly processed or after overnight conservation at 4 °C. Using this method, we confirmed the repeatedly reported obesity-associated mitochondrial dysfunction in the heart and extended it to the lungs. We set up and validated a new strategy to optimally assess mitochondrial function in murine tissues. As such, this method is of great potential interest for monitoring mitochondrial function in cohort samples.  相似文献   
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An X‐ray crystal structure of Kelch‐like ECH‐associated protein (Keap1) co‐crystallised with (1S,2R)‐2‐[(1S)‐1‐[(1,3‐dioxo‐2,3‐dihydro‐1H‐isoindol‐2‐yl)methyl]‐1,2,3,4‐tetrahydroisoquinolin‐2‐carbonyl]cyclohexane‐1‐carboxylic acid (compound (S,R,S)‐ 1 a ) was obtained. This X‐ray crystal structure provides breakthrough experimental evidence for the true binding mode of the hit compound (S,R,S)‐ 1 a , as the ligand orientation was found to differ from that of the initial docking model, which was available at the start of the project. Crystallographic elucidation of this binding mode helped to focus and drive the drug design process more effectively and efficiently.  相似文献   
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[Correction Notice: An erratum for this article was reported in Vol 3(1) of Psychological Trauma: Theory, Research, Practice, and Policy (see record 2010-26899-001). There were citation errors in the last sentence of the first column of text on page 9, and a reference was omitted from the reference list. The sentence should have read: “This result is consistent with other work that has found support for the anxious and dissociative reaction associated with trauma among Latinos and how it may relate to “ataque de nervios” (Hinton, Chong, Pollack, Barlow, & McNally, 2008; Lewis-Fernandez et al., 2002; Schechter et al., 2000; Tolin, Robinson, Gaztambide, Horowitz, & Blank, 2007).] [Correction Notice: An erratum for this article was reported in of Psychological Trauma: Theory, Research, Practice, and Policy (see record 2010-26899-001). In the original article there were citation errors in the last sentence of the first column of text on page 9, and a reference was omitted from the reference list. The sentence should have read: “This result is consistent with other work that has found support for the anxious and dissociative reaction associated with trauma among Latinos and how it may relate to “ataque de nervios” (Hinton, Chong, Pollack, Barlow, & McNally, 2008; Lewis-Fernandez et al., 2002; Schechter et al., 2000; Tolin, Robinson, Gaztambide, Horowitz, & Blank, 2007).] Research on the victimization of Latino women and the subsequent psychological impact has been limited by focusing on individual forms of victimization, primarily partner violence or sexual assault. Another deficiency includes mainly using convenience and/or geographically restricted samples, which impacts the generalizability of the results. To overcome these research limitations, the Sexual Assault Among Latinas (SALAS) study aimed to evaluate the broader scope of victimization among Latino women. The study surveyed a national sample of 2,000 Latino women using random digit dial methodology. Women were asked about various forms of victimization in childhood and adulthood including physical assaults, sexual assaults, stalking, threats, and witnessed violence, as well as psychological symptomatology including depression, anxiety, anger, and dissociation. This analysis found that victimized women were more likely to experience some form of polyvictimization and/or revictimization throughout their lives, with only 36% of victimized women experiencing one form of victimization in childhood or adulthood alone. Furthermore, multiple victimization experiences significantly increased the proportion of women who experienced psychological distress symptoms in the clinical range. For almost all evaluated symptoms, the multiple forms of victimization or varying victimization patterns significantly predicted clinical levels of psychological distress over any specific form or single incident of victimization. The results suggest that victimized Latino women experience multiple forms of victimization and that the evaluation of a broader spectrum of victimization better accounts for pathological symptomatology. Clinical implications for Latino women and future research directions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
19.
This review focuses on the role of oestrogen in male sexual behaviour using oestrogen receptor alpha and beta knockout (ERalphaKO and ERbetaKO) mouse models. ERbetaKO mice are capable of mating and producing offspring, whereas ERalphaKO mice are unable to do either. When ERalphaKO males are treated with testosterone or dihydrotestosterone (DHT), < 50% display mounting behaviour, few intromit and none ejaculate. However, concurrent treatment with testosterone and a dopamine agonist instates masculine sexual behaviour in both male and female ERalphaKO mice. Dopamine content in the preoptic area and associated regions is not affected by oestrogen receptor alpha gene disruption. However, expression of neuronal nitric oxide synthase immunoreactivity is severely reduced in ERalphaKO males compared with wild-type males. These findings, together with studies conducted in aromatase knockout mice, are at odds with the dogma that oestrogen is required during development for expression of male sexual behaviour in adults. However, they do support a role for oestrogens, mediated by oestrogen receptor alpha, in regulation and production of neuronal nitric oxide synthase, which in turn may control dopamine agonist release. As has been shown in male rats, in mice dopamine agonist release is likely to be an essential component of the neural pathway that mediates male sexual behaviour.  相似文献   
20.
Taking advantage of a large multiyear data set of synthetic aperture radar (SAR) and ground observations collected in Belgium, this research aims at improving the understanding of the SAR signal sensitivity to crop growth by means of water cloud model (WCM) inversion for retrieving maize leaf area index (LAI) from C-band and VV-polarized SAR data. The results show that at intermediate moisture levels, the contributions of both soil and plants to the SAR response are confused as, to the SAR sensor, the vegetation seems to behave as bare soil of about 21% water content. Moreover, as the WCM usually required a calibration every year, this research assessed the robustness of the calibrated WCM by model cross-validation between years for maize. Ten different calibrations and inversions of the WCM were completed based on three years of observations. Two other years of observation serve as independent data sets to calculate the LAI retrieval error. The results demonstrate the capability of transferring the model calibration to independent subsequent crop seasons with an acceptable performance reduction.  相似文献   
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