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1.
Miyahara Daiki Ueda Itaru Hayashi Yu-ichi Mizuki Takaaki Sone Hideaki 《International Journal of Information Security》2021,20(5):729-740
International Journal of Information Security - Card-based cryptography is an attractive and unconventional computation model; it provides secure computing methods using a deck of physical cards.... 相似文献
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This paper proposes a synthesis method of gain‐scheduled control systems that switch linear time‐invariant controllers according to hysteresis of the scheduling parameter. Stability and L2‐gain analysis and synthesis methods for switched systems are applied to the switched gain‐scheduled control synthesis using reset of the controller state, where also the reset law is computed via linear matrix inequalities (LMIs). In addition to optimization of an upper bound of L2‐gain, we reduce jumps of control input via an auxiliary optimization. Numerical examples are presented to illustrate the switched gain‐scheduled controller. 相似文献
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Naoki Motomura Yuto Yamazaki Daiki Koga Shogo Harashima Xin Gao Yuta Tezuka Kei Omata Yoshikiyo Ono Ryo Morimoto Fumitoshi Satoh Yasuhiro Nakamura Go Eun Kwon Man Ho Choi Akihiro Ito Hironobu Sasano 《International journal of molecular sciences》2022,23(4)
Cortisol-producing adenoma (CPA) is composed of clear and compact cells. Clear cells are lipid abundant, and compact ones lipid poor but associated with higher production of steroid hormones. PRKACA mutation (PRKACA mt) in CPA patients was reported to be associated with more pronounced clinical manifestation of Cushing’s syndrome. In this study, we examined the association of histological features and genotypes with cholesterol uptake receptors and synthetic enzymes in 40 CPA cases, and with the quantitative results obtained by gas chromatography-mass spectrometry (GC-MS) analysis in 33 cases to explore their biological and clinical significance. Both cholesterol uptake receptors and synthetic enzymes were more abundant in compact cells. GC-MS analysis demonstrated that the percentage of compact cells was inversely correlated with the concentrations of cholesterol and cholesterol esters, and positively with the activity of cholesterol biosynthesis from cholesterol esters. In addition, hormone-sensitive lipase (HSL), which catalyzes cholesterol biosynthesis from cholesterol esters, tended to be more abundant in compact cells of PRKACA mt CPAs. These results demonstrated that both cholesterol uptake and biosynthesis were more pronounced in compact cells in CPA. In addition, more pronounced HSL expression in compact cells of PRKACA mt CPA could contribute to their more pronounced clinical manifestation. 相似文献
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Maeda-Yamamoto M Saito T Nesumi A Tokuda Y Ema K Honma D Ogino A Monobe M Murakami A Murakami A Tachibana H 《Journal of the science of food and agriculture》2012,92(11):2379-2386
BACKGROUND: The purpose of this study was to evaluate the effects of leaf order or crop season on anthocyanins and other chemicals in the anthocyanin‐rich tea cultivar ‘Sunrouge’ (Camellia sinensis x C. taliensis) by using high‐performance liquid chromatography, and to study the effect of ‘Sunrouge’ extract on acetylcholinesterase (AChE) activity in human neuroblastoma SK‐N‐SH cells. RESULTS: The total anthocyanin content was higher in the third (3.09 mg g?1) than in the second (2.24 mg g?1) or first crop season (1.79 mg g?1). The amount of anthocyanins contained in the stem was high (1.61 mg g?1). In the third crop season, the concentrations of delphinidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside (DCGa), cyanidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside, delphinidin‐3‐O‐β‐D ‐galactopyranoside, delphinidin‐3‐O‐β‐D ‐(6‐O‐(Z)‐p‐coumaroyl)galactopyranoside, cyanidin‐3‐O‐β‐D ‐galactoside, and delphinidin‐3‐O‐β‐D ‐glucoside were 1.57 mg g?1, 0.52 mg g?1, 0.40 mg g?1, 0.22 mg g?1, 0.14 mg g?1, and 0.11 mg g?1, respectively. DCGa accounted for about 50% of the anthocyanins present. The suppressive effect of ‘Sunrouge’ water extract on AChE activity in human neuroblastoma SK‐N‐SH cells was the strongest among the three tea cultivars (‘Sunrouge’, ‘Yabukita’ and ‘Benifuuki’). CONCLUSION: These results suggested that ‘Sunrouge’ might protect humans from humans from AChE‐related diseases by suppressing AChE activity. To obtain sufficient amounts of anthocyanins, catechins and/or caffeine for a functional food material, ‘Sunrouge’ from the third crop season should be used. Copyright © 2012 Society of Chemical Industry 相似文献
8.
Yang Gao Junya Iihama Daiki Hamana Ryo Iwasaki Sawao Honda Toru Asaka Munni Kumari Tomokatsu Hayakawa Samuel Bernard Philippe Thomas Yuji Iwamoto 《International Journal of Applied Ceramic Technology》2023,20(2):768-779
A series of β-SiAlON:Eu2+ phosphors were synthesized from single-source precursors, perhydropolysilazane chemically modified with Al(OCH(CH3)2)3, AlCl3, and EuCl2. The single-source precursors were converted to β-SiAlON:Eu2+ phosphors by pyrolysis under flowing N2 or NH3 at 1000°C, followed by heat treatment at 1800°C under an N2 gas pressure at 980 kPa. By varying the molar ratio of the chemical modifiers, β-SiAlON:Eu2+ with the compositions close to the theoretical ones expressed as Si6−zAlzOz−2yN8−z+2y:yEu2+ were synthesized, where the z values and Eu2+ contents were controlled in the ranges of .44–.78 and .35–1.48 mol%, respectively. The polymer-derived β-SiAlON:Eu2+ phosphors exhibited green emission under excitation at 460 nm attributed to the 4f7–4f6(7f3)5d1 transition of dopant Eu2+. High-angle annular dark-field-scanning transmission microscopy analysis confirmed that the doped-Eu2+ existed interstitially within the channels along the c axis of host β-SiAlON. Compared with the conventional powder metallurgy route, the polymer-derived ceramic route in this study offers some advantages in the grain growth of host β-SiAlON and photoluminescence properties in terms of green emission intensity under excitation at 460 nm, and the highest intensity was achieved for the polymer-derived β-SiAlON:Eu2+ with z = .64 and .37 mol% Eu2+. 相似文献
9.
Sina Naficy Shota Kawakami Sasha Sadegholvaad Minato Wakisaka Geoffrey M. Spinks 《应用聚合物科学杂志》2013,130(4):2504-2513
Hydrogels are polymer networks swollen in water. Because of their soft and wet nature, and their ability to show large volume changes, hydrogels can be useful in many biomedical and actuator applications. In these applications, it is crucial to tune the mechanical and physical properties of a hydrogel in a controllable manner. Here, interpenetrating polymer networks (IPNs) made of a covalently crosslinked network and an ionically crosslinked network were produced to investigate the effective parameters that control the physical and mechanical properties of an IPN hydrogel. Covalently crosslinked polyacrylamide (PAAm) or poly(acrylic acid) (PAA) networks were produced in the presence of alginate (Alg) that was then ionically crosslinked to produce the IPN hydrogels. The effect of ionic crosslinking, degree of covalent crosslinking, AAm : Alg and AA : Alg ratio on the swelling ratio, tensile properties, indentation modulus, and fracture energy of IPN hydrogels was studied. A hollow cylindrical hydrogel with gradient mechanical properties along its length was developed based on the obtained results. The middle section of this hydrogel was designed as a pH triggered artificial muscle, while each end was formulated to be harder, tougher, and insensitive to pH so as to function as a tendon‐like material securing the gel muscle to its mechanical supports. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2504–2513, 2013 相似文献
10.
Preparation of porous membranes by selective decomposition of adamantane unit in ABA‐type triblock copolymer 下载免费PDF全文
The mechanism of pore formation by selective decomposition of adamantane unit in an ABA‐type triblock copolymer derived from 4,4‐(hexafluoroisopropylidene)diphthalic anhydride‐2,3,5,6‐tetramethyl‐1,4‐phenylenediamine (6FDA‐TeMPD) and poly(2‐methyl‐2‐adamantylmethacrylate) (PMAdMA) was investigated on this basis. This study aims to developing a novel method of material design for high‐precision gas separation membranes and application to electric devices by improving dielectric constant. Scanning electron microscopy images showed that the membrane structure changed considerably after heating; the difference increased with the increase in adamantane content. Interestingly, the internal structure of Block(36 mol%6FDA‐TeMPD/64 mol%PMAdMA) membrane was almost unchanged although its surface structure was changed. These results suggest that the mechanism of formation of porous membrane involves the decomposition of adamantane unit from surface. In addition, more adamantane units inside the membrane were discharged to the surface of the membrane through a path formed by decomposed adamantane units. POLYM. ENG. SCI., 56:1191–1200, 2016. © 2016 Society of Plastics Engineers 相似文献