全文获取类型
收费全文 | 549篇 |
免费 | 67篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 12篇 |
综合类 | 8篇 |
化学工业 | 137篇 |
金属工艺 | 24篇 |
机械仪表 | 35篇 |
建筑科学 | 28篇 |
矿业工程 | 17篇 |
能源动力 | 12篇 |
轻工业 | 56篇 |
水利工程 | 7篇 |
石油天然气 | 16篇 |
武器工业 | 3篇 |
无线电 | 94篇 |
一般工业技术 | 112篇 |
冶金工业 | 30篇 |
原子能技术 | 2篇 |
自动化技术 | 31篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 21篇 |
2020年 | 10篇 |
2019年 | 18篇 |
2018年 | 22篇 |
2017年 | 20篇 |
2016年 | 21篇 |
2015年 | 29篇 |
2014年 | 30篇 |
2013年 | 45篇 |
2012年 | 39篇 |
2011年 | 46篇 |
2010年 | 32篇 |
2009年 | 41篇 |
2008年 | 28篇 |
2007年 | 29篇 |
2006年 | 22篇 |
2005年 | 15篇 |
2004年 | 15篇 |
2003年 | 14篇 |
2002年 | 16篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 4篇 |
1998年 | 13篇 |
1997年 | 10篇 |
1996年 | 4篇 |
1995年 | 11篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有624条查询结果,搜索用时 15 毫秒
71.
The effects of oleic acid and lauric acid in a mixture of fatty alcohol and propylene glycol (FAPG base) on the percutaneous absorption of fluocinolone acetonide (FA) were investigated by using nude mouse skin and synthetic membrane in vitro. me mixture of 0.9% sodium chloride and methanol (91) was used as the receptor phase for the diffusion study. The concentration of FA in the receptor phase was determined by HPLC. fie optimal formulation of the FAPG base was obtained with the addition of 5% lauric acid 相似文献
72.
Hun Soo Jang Bokyeong Son Hui Song Gun Young Jung Heung Cho Ko 《Journal of Materials Science》2014,49(23):8000-8009
In this study, we demonstrate a method for creating multi-length-scale ZnO nanowires in a controllable manner on diverse planar and curvilinear substrates by introducing immiscible liquid masking layers (LMLs) above and beneath a nutrient solution used in hydrothermal growth. The confinement of volatile reactants by the LMLs stabilizes the pH, which is an important parameter in determining the shape of the nanowires, to enable growth in a stable manner. The conformal wettability of the LMLs provides freedom in the choice of target substrates and allows for the possibility of mounting spatially moving stages without the use of a specially designed solid lid. Selective growth within the growth zone defined by the LMLs in a dynamic- and/or static-mode can create various types of ZnO nanowires with gradual or terraced length profiles in two- or three-dimensional geometries. For a device application, we developed cylindrical photodetectors with the configuration of Cr/ZnO seed/ZnO nanowires/poly(3-hexylthiophene-2,5-diyl)/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) to show the ability to spatially modulate the photo-sensitivity by controlled hydrothermal growth of diverse length scales of ZnO nanowires using the LML method. 相似文献
73.
74.
75.
Self‐Powered Cardiac Pacemaker Enabled by Flexible Single Crystalline PMN‐PT Piezoelectric Energy Harvester 下载免费PDF全文
76.
A vertically aligned anatase TiO2 (A-TiO2) nanotube array has been fabricated by coating a ZnO nanorod (NR) template with a TiO2 precursor solution. After coating, the ZnO NR cores were selectively etched in an acidic environment to form TiO2 nanotubes (NTs). More specifically, after growing the ZnO NRs via a hydrothermal method, one drop of the TiO2 precursor solution was cast to coat the ZnO NRs, the tops of which were previously covered with chemical capping materials by electrostatic interaction, and then the sample was sintered. Finally, the sample was immersed in an acidic solution resulting in selective etching of the ZnO NR cores. Thus, only TiO2 NTs remained on the substrate. The capping material is effectively used to create a perfect, hexagonal open-ended TiO2 NT array, which interestingly extends onset absorption towards the visible region. 相似文献
77.
Clinical and psychosocial factors predicting health‐related quality of life in hemodialysis patients 下载免费PDF全文
Gun Woo Kang In Hee Lee Ki Sung Ahn Jonghun Lee Yunmi Ji Jungmin Woo 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(3):439-446
Many patients with end‐stage renal disease have significant impairment in health‐related quality of life (HRQoL). Most previous studies have focused on clinical factors; however, quality of life can also be affected by psychosocial factors. The aim of this study was to identify the possible predictors of HRQoL among clinical and psychosocial factors in hemodialysis (HD) patients. The study included 101 patients who were undergoing HD. Psychosocial factors were evaluated using the Hospital Anxiety and Depression Scale, Multidimensional Scale of Perceived Social Support, Montreal Cognitive Assessment, and Pittsburgh Sleep Quality Index. We also assessed laboratory and clinical factors, including albumin, Kt/V as a marker of dialysis adequacy, normalized protein catabolic rate, and duration of HD. The Euro Quality of Life Questionnaire 5‐Dimensional Classification (EQ‐5D) was used to evaluate HRQoL. The mean EQ‐5D index score was 0.704 ± 0.199. The following variables showed a significant association with the EQ‐5D index: age (P < 0.001), depression (P < 0.001), anxiety (P < 0.001), support from friends (P < 0.001), cognitive function (P < 0.001), duration of HD (P = 0.034), triglyceride (P = 0.031), total iron‐binding capacity (P = 0.036), and phosphorus (P = 0.037). Multiple regression analysis showed that age (95% confidence interval [CI] ?0.008 to ?0.002), anxiety (95% CI ?0.025 to ?0.009), and support from friends (95% CI 0.004 to 0.018) were independent predictors of impaired HRQoL. This study explored determinants of impaired HRQoL in HD patients. We found that impaired HRQoL was independently associated with age, anxiety, and support from friends. We should consider psychosocial as well as clinical factors when evaluating ways to improve HRQoL in HD patients. 相似文献
78.
Metal‐Etching‐Free Direct Delamination and Transfer of Single‐Layer Graphene with a High Degree of Freedom 下载免费PDF全文
79.
80.
Jae Young Sim Gun Ho Lee Shin‐Hyun Kim 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(37):4938-4945
Colloidal photonic structures have been designed to have granular format to use them for paint pigments, encoded carriers, and display pixels. However, conventional approaches only provide spherical or discoid shapes, restricting their applications. Cylindrical granules with fan‐shaped compartments in the cross section are appealing for microcarriers with abundant optical codes and active display pigments for color switching. In this work, a stratified laminar flow of concentrated silica particles is employed, formed in a cylindrical microchannel, to produce cylindrical photonic microparticles with multiple compartments. To accomplish this, a microfluidic device is designed to have one cylindrical main channel connected with four branch channels. Four different photocurable suspensions are independently injected through the branches to form quarter‐cylindrically compartmentalized streams in the main channel. Local ultraviolet irradiation on the main channel polymerizes the suspension, thereby forming cylindrical microparticles with four compartments. In each compartment, silica particles form ordered array which develops particle size–dependent structural color. Therefore, different colors can be incorporated into single microcylinder by employing different sizes of silica particles. Moreover, one of the compartments can be rendered to be magnetoresponsive by embedding aligned magnetic particles, which enables the remote control of microcylinder orientation and therefore the switching of structural colors. 相似文献