全文获取类型
收费全文 | 934篇 |
免费 | 68篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 3篇 |
综合类 | 2篇 |
化学工业 | 327篇 |
金属工艺 | 39篇 |
机械仪表 | 22篇 |
建筑科学 | 24篇 |
矿业工程 | 2篇 |
能源动力 | 42篇 |
轻工业 | 56篇 |
水利工程 | 5篇 |
石油天然气 | 2篇 |
无线电 | 71篇 |
一般工业技术 | 166篇 |
冶金工业 | 20篇 |
原子能技术 | 2篇 |
自动化技术 | 221篇 |
出版年
2023年 | 7篇 |
2022年 | 52篇 |
2021年 | 92篇 |
2020年 | 33篇 |
2019年 | 41篇 |
2018年 | 47篇 |
2017年 | 25篇 |
2016年 | 46篇 |
2015年 | 33篇 |
2014年 | 51篇 |
2013年 | 75篇 |
2012年 | 53篇 |
2011年 | 64篇 |
2010年 | 38篇 |
2009年 | 52篇 |
2008年 | 40篇 |
2007年 | 36篇 |
2006年 | 29篇 |
2005年 | 20篇 |
2004年 | 19篇 |
2003年 | 20篇 |
2002年 | 20篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 7篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 6篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1973年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1004条查询结果,搜索用时 0 毫秒
111.
Krzysztof Krawczyk Alicja Szabelska-Bersewicz Sebastian Wojciech Przemieniecki Mateusz Szymaczyk Aleksandra Obrpalska-Stplowska 《International journal of molecular sciences》2022,23(21)
Simple SummaryA new sources of plant growth-promoting (PGP) bacteria are needed to increase the agricultural crops without increasing the usage of chemicals. The aim of this study was to test the hypothesis that insect-gut bacteria promote tomato plant growth. The insect gut bacteria were screened for the presence of PGP traits. The plants treated with bacterial consortium showed a significant increase in fruit yield, in both number of fruits (+41%) and weight of fruits (+44%). Our results showed that: (i) D. virgifera gut’s bacteria significantly promote the growth of tomato plants, and (ii) bacteria other than plant-related can be considered as PGP. It must be underlined that even though the insect gut bacteria were proven to stimulate the plant’s growth, their practical usage must be preceded by an examination of their influence on ecological and biological safety.AbstractWe investigated gut bacteria from three insect species for the presence of plant growth properties (PGP). Out of 146 bacterial strains obtained from 20 adult specimens of Scolytidae sp., 50 specimens of Oulema melanopus, and 150 specimens of Diabrotica virgifera, we selected 11 strains displaying the following: PGP, phosphate solubility, production of cellulase, siderophore, lipase, protease, and hydrogen cyanide. The strains were tested for growth promotion ability on tomato (Lycopersicon esculentum) plants. Each strain was tested individually, and all strains were tested together as a bacterial consortium. Tomato fruit yield was compared with the negative control. The plants treated with bacterial consortium showed a significant increase in fruit yield, in both number of fruits (+41%) and weight of fruits (+44%). The second highest yield was obtained for treatment with Serratia liquefaciens Dv032 strain, where the number and weight of yielded fruits increased by 35% and 30%, respectively. All selected 11 strains were obtained from Western Corn Rootworm (WCR), Diabrotica virgifera. The consortium comprised: Ewingella americana, Lactococcus garvieae, L. lactis, Pseudomonas putida, Serratia liquefaciens, and S. plymuthica. To our knowledge, this is the first successful application of D. virgifera gut bacteria for tomato plant growth stimulation that has been described. 相似文献
112.
Klaudia Kwieciska Anna Stachowicz-Kunierz Beata Korchowiec Maciej Roman Wojciech M. Kwiatek Anna Jagusiak Irena Roterman Jacek Korchowiec 《International journal of molecular sciences》2022,23(16)
The uptake and distribution of doxorubicin in the MCF7 line of breast-cancer cells were monitored by Raman measurements. It was demonstrated that bioavailability of doxorubicin can be significantly enhanced by applying Congo red. To understand the mechanism of doxorubicin delivery by Congo red supramolecular carriers, additional monolayer measurements and molecular dynamics simulations on model membranes were undertaken. Acting as molecular scissors, Congo red particles cut doxorubicin aggregates and incorporated them into small-sized Congo red clusters. The mixed doxorubicin/Congo red clusters were adsorbed to the hydrophilic part of the model membrane. Such behavior promoted transfer through the membrane. 相似文献
113.
Tomasz Tuzimski Szymon Szubartowski Aleksandra Stupak Wojciech Kwaniewski Magorzata Szultka-Myska Anna Kwaniewska Bogusaw Buszewski 《International journal of molecular sciences》2023,24(1)
The present study aimed to investigate the relationship between the concentrations of bisphenols residues in the amniotic fluid (AF) samples collected during amniocentesis and fetal chromosomal abnormalities in pregnant women. A total of 33 pregnant Polish women aged between 24 and 44 years, and screened to detect high risk for chromosomal defects in the first trimester, were included in this study. Samples were collected from these patients during routine diagnostic and treatment procedures at mid-gestation. The concentrations of various bisphenols residues in the samples were determined by liquid chromatography coupled with triple quadrupole tandem mass spectrometry (LC-ESI-QqQ-MS/MS). Residues of eight analytes (BPS, BPF, BPA, BPAF, BADGE, BADGE•2H2O, BADGE•H2O•HCl and BADGE•2HCl) were detected in amniotic fluid samples in the range 0.69 ng/mL to 3.38 ng/mL. Fetuses with chromosomal abnormalities showed a slightly higher frequency of occurrence of selected bisphenols residues in the AF samples collected between 15–26 weeks of pregnancies. Finally, the proposed method was applied in the simultaneous determination of several endocrine-disrupting chemicals from bisphenol group in 33 human AF samples. BADGE•H2O•HCl has been identified in the AF samples taken from women older than average in the examined group. The number of detected compounds has been significant for the following analytes: BPS, BPAF, BADGE•H2O•HCl and BADGE. The proposed method may be an attractive alternative for application in large-scale human biomonitoring studies. 相似文献
114.
Jan Novák Derek Nowrouzezahrai Carsten Dachsbacher Wojciech Jarosz 《Computer Graphics Forum》2012,31(4):1407-1413
A recent technique that forms virtual ray lights (VRLs) from path segments in media, reduces the artifacts common to VPL approaches in participating media, however, distracting singularities still remain. We present Virtual Beam Lights (VBLs), a progressive many‐lights algorithm for rendering complex indirect transport paths in, from, and to media. VBLs are efficient and can handle heterogeneous media, anisotropic scattering, and moderately glossy surfaces, while provably converging to ground truth. We inflate ray lights into beam lights with finite thicknesses to eliminate the remaining singularities. Furthermore, we devise several practical schemes for importance sampling the various transport contributions between camera rays, light rays, and surface points. VBLs produce artifact‐free images faster than VRLs, especially when glossy surfaces and/or anisotropic phase functions are present. Lastly, we employ a progressive thickness reduction scheme for VBLs in order to render results that converge to ground truth. 相似文献
115.
Wojciech Ciesielski & Piotr Tomasik 《International Journal of Food Science & Technology》2004,39(6):691-698
It was shown that potato starch formed Werner‐type complexes. In these complexes a metal atom is ligated by the lone electron pairs of hydroxyl groups from d ‐glucose units and phosphate groups in starch. Acetate, chloride and nitrate were counter‐ions to the transition metal atoms. The metal cations bound preferentially to the phosphoric acid moiety of amylopectin, but secondarily they were co‐ordinated by the hydroxyl groups of the d ‐glucose units. This resulted in the formation of clathrate cages in which a significant number of the water molecules were trapped. Such structures were able to co‐ordinate further metal cations. Only Mn(II) and Co(II) ions, with acetate counter‐ions, neither formed clathrate cages nor were co‐ordinated by the hydroxyl groups of the d ‐glucose of starch. 相似文献
116.
Zenon Foltynowicz Wojciech Kozak Ryszard Fiedorow 《Packaging Technology and Science》2002,15(2):75-81
Temperature‐programmed reduction (TPR) measurements were performed for iron oxalates, iron(III) hydroxide (both pure and with additives) and iron(II, III) oxide. On the ground of TPR curves, reduction temperatures of the iron‐containing parent substances were chosen followed by oxygen uptake determination. Comparison of oxygen uptakes points to the use of Fe(OH)3 and Fe3O4 as more advantageous than that of iron oxalates. Co‐precipitation from a mixed solution of iron and manganese salts results in a product which is more resistant to particle agglomeration at elevated temperatures than that obtained byprecipitation from solution of iron salt alone. Copyright © 2002 JohnWiley & Sons, Ltd. 相似文献
117.
Tomasz Czeppe Wojciech Zakulski Elbieta Bielaska 《Journal of Phase Equilibria and Diffusion》2003,24(3):249-254
A part of the Al-Mg phase diagram was studied in the range of composition between 48 and 61 at.% Al by DSC and SEM/EDS methods.
The temperature ranges of stability of the β, γ, and ɛ phases were considered. It was found that the congruent melting temperature
of the β phase was 450±1 °C. The Al content in that phase was determined to be 61±1 at.% Al at 420 °C. The upper temperature
limit of the stability of the ɛ phase was established to be 427±1 °C. The Al content changed from 54 at.% at 390 °C to 56
at.% at 420 °C. The lower temperature limit of the ɛ phase formation was not determined, as a result of a slow ɛ=β+γ reaction.
The hypothetical λ or ζ phases were not found, but it was observed that decomposition of oxides might produce extra thermal
effects. 相似文献
118.
Determination of the ash yield and the mineral matter content of brown coals by density measurements
Edward Chruściel Wit Jagusztyn Andrzej Kreft Andrzej Lenda Wojciech Przybylowicz Jan Woźniak 《Fuel》1983,62(3):389-390
A method of measuring the density of bed-moist brown coals based on their plastic properties is described and the feasibility of using the method for determination of the ash yield of the coal is evaluated. 相似文献
119.
120.
Wojciech Pietraszkiewicz Janusz Badur 《International Journal of Engineering Science》1983,21(9):1097-1115
Finite rotations in continuum mechanics are described by means of either a proper orthogonal tensor or finite rotation vectors. Some algebraic relations concerning the finite rotations are reviewed. Formulae expressing them in terms of displacements are given. Along each of the curvilinear coordinate lines the finite rotations are shown to satisfy some systems of the linear first-order differential equations. Each system of the equations is presented in four different but equivalent forms associated with an intermediate stretched basis or with an intermediate rotated basis. Integrability conditions of the system of equations provide various alternative forms of compatibility conditions in continuum mechanics. The displacement field is expressed through the stretch and rotation fields in the form of three successive line integrals. The formula describes the displacements to within a constant finite translation and a constant finite rotation. The procedure proposed here generalizes the formula derived by Cesàro (1906) within the classical linear theory of elasticity. 相似文献