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排序方式: 共有491条查询结果,搜索用时 15 毫秒
91.
Rachel Novotny Claudio Nigg Katalina McGlone Gloria Renda Noah Jung Masako Matsunaga Njeri Karanja 《Food chemistry》2013
The Pacific Tracker (PacTrac) is a computer program designed to analyse food intakes of individuals from the Pacific Region. PacTrac’s original output included servings of daily intake of food groups according to the United States Food Guide Pyramid, nutrient intake recommendations, and a comparison to other national nutrition recommendations. PacTrac was made available for public use through the Hawaii Foods website (hawaiifoods.hawaii.edu). PacTrac2 is an updated and expanded version of PacTrac that uses the United States MyPyramid/MyPlate food groups in household units of daily intake, rather than servings. In addition, the PacTrac2 includes a physical activity analysis tool which quantifies minutes of physical activities and their intensities based on energy estimates from the compendium of physical activity and research on children. An Expert System (ES) – a computerised decision tree to guide behaviour change – was developed using information on self-efficacy and stage of readiness to change, and the fruit and vegetable intake and physical activity information from PacTrac2. The ES produces reports for the child, the parent/guardian, and the child’s physician with child-specific strategies, targeted behavioural information, and feedback tailored to the child. PacTrac2-ES was designed for the Pacific Kids DASH for Health (PacDASH) intervention study, conducted in the Kaiser Permanente health care system in Hawaii. The intervention is based on the child’s self-efficacy and stage of readiness to change intake of fruits and vegetables and physical activity, with a goal of maintaining body weight to prevent obesity. The intervention is complemented with stage-based mailers addressing the environment for physical activity and fruit and vegetable intake and newsletters that address related behaviours (sedentary activity and a DASH eating approach). This project is the first to expand the PacTrac to contain children’s foods and physical activities from the Pacific Region and to use current US MyPyramid/MyPlate food and physical activity analysis and guidance systems, and to develop and implement an Expert System for fruits, vegetables and physical activity of 5–8-year-old children. The PacTrac2-ES was used in the PacDASH study and will be used for other programs to promote healthy eating and physical activity of children in the Pacific Region. 相似文献
92.
The gaseous diffusion coefficients of methyl bromide (CH3Br) and methyl iodide (CH3I) into dry air, nitrogen, and oxygen have been measured in the temperature range 303–453 K and at atmospheric pressure via the Taylor dispersion method. Both for methyl bromide and methyl iodide, the diffusion coefficients do not vary in practice on substituting pure nitrogen or oxygen for dry air. The diffusion coefficients for methyl iodide are systematically smaller than those for methyl bromide by about 11%. For the methyl iodide‐oxygen system, the effect of the thermal decomposition of methyl iodide has been observed at 453 K. The present results can be reproduced well by the functional form D = ATB, where D (cm2s?1) is the diffusion coefficient at 101 325 Pa (1 atm) and T (K) is the absolute temperature. The constants A and B are as follows: methyl bromide‐(air, nitrogen, oxygen), A = 5.57 × 10?6, B = 1.76; methyl iodide‐(air, nitrogen, oxygen), A = 5.26 × 10?6, B = 1.75. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20255 相似文献
93.
Natural frequencies and buckling stresses of angle-ply laminated composite plates are analyzed by taking into account the effects of shear deformation, thickness change and rotatory inertia. By using the method of power series expansion of displacement components, a set of fundamental dynamic equations of a two-dimensional higher-order theory for thick rectangular laminates subjected to in-plane stresses is derived through Hamilton's principle. Several sets of truncated approximate theories are applied to solve the eigenvalue problems of a simply supported thick laminated plate. In order to assure the accuracy of the present theory, convergence properties of the fundamental natural frequency are examined in detail. Numerical results are compared with those of the published existing theories. The modal displacement and stress distributions in the thickness direction are obtained and plotted in figures. The present global higher-order approximate theories can predict the natural frequencies, buckling stresses and modal stresses of thick multilayered angle-ply composite laminates accurately within small number of unknowns which is not dependent on the number of layers. 相似文献
94.
Hiroyuki Matsunaga 《Canadian Metallurgical Quarterly》2000,126(1):27-34
Natural frequencies and buckling stresses of a thick isotropic plate on two-parameter elastic foundations are analyzed by taking into account the effect of shear deformation, thickness change, and rotatory inertia. Using the method of power series expansion of the displacement components, a set of fundamental dynamic equations of a two-dimensional, higher-order theory for thick rectangular plates subjected to in-plane stresses is derived through Hamilton's principle. Several sets of truncated approximate theories are used to solve the eigenvalue problems of a simply supported thick elastic plate. To assure the accuracy of the present theory, convergence properties of the minimum natural frequency and the buckling stress are examined in detail. The distribution of modal transverse stresses are obtained by integrating the three-dimensional equations of motion in the thickness direction. The present approximate theories can accurately predict the natural frequencies and buckling stresses of thick plates on elastic foundations as compared with Mindlin plate theory and classical plate theory. 相似文献
95.
The addition of hollow fillers having appropriate mechanical properties can decrease the density of the resulting composite,
called syntactic foams, while concurrently improving its mechanical properties. In this study, hollow fly ash particles, called
cenospheres, are used as fillers in polyester matrix material. Cenospheres are a waste by-product of coal combustion and,
as such, are available at very low cost. In this study, the composites were synthesized by settling cenospheres in a glass
tube filled with liquid polyester resin and subsequently curing the resin. This process resulted in a functionally graded
structure containing a gradient in the cenosphere volume fraction along the sample height. Uniform radial sections were cut
from each composite and were characterized to observe the relationship between cenosphere volume fraction and compressive
properties of the composite. The composite was also tested using ultrasonic non-destructive evaluation method. Results show
that the modulus of the composites increases with increasing cenosphere volume fraction. The modulus of composites containing
more than 4.9 vol% cenosphere was found to be higher than the matrix resin. In general, the modulus of composites increased
from 1.33 to 2.1 GPa for composites containing from 4.9–29.5 vol% cenospheres. The specific strength of the composite was
found to be as high as 2.03 MPa/(kg/m3) compared to 0.96 MPa/(kg/m3) for the neat resin. Numerous defects present in fly ash particles caused a reduction in the strength of the composite. However,
the reduction in the strength was found to be only up to 22%. Increase of over 110% in the specific modulus and only a slight
decrease in the strength indicates the possibility of significant saving of weight in the structures using polyester/fly ash
syntactic foams. 相似文献
96.
97.
Feunai Agape Papalii Tautau Minoru Izumi Emiko Matsunaga Yujiro Higuchi Kaoru Takegawa 《Journal of Applied Glycoscience》2020,67(3):87
α-L-Rhamnosidases (α-L-Rha-ases, EC 3.2.1.40) are glycosyl hydrolases (GHs) that hydrolyze a terminal α-linked L-rhamnose residue from a wide spectrum of substrates such as heteropolysaccharides, glycosylated proteins, and natural flavonoids. As a result, they are considered catalysts of interest for various biotechnological applications. α-L-rhamnose (6-deoxy-L-mannose) is structurally similar to the rare sugar α-L-mannose. Here we have examined whether microbial α-L-Rha-ases possess α-L-mannosidase activity by synthesizing the substrate 4-nitrophenyl α-L-mannopyranoside. Four α-L-Rha-ases from GH78 and GH106 families were expressed and purified from Escherichia coli cells. All four enzymes exhibited both α-L-rhamnosyl-hydrolyzing activity and weak α-L-mannosyl-hydrolyzing activity. SpRhaM, a GH106 family α-L-Rha-ase from Sphingomonas paucimobilis FP2001, was found to have relatively higher α-L-mannosidase activity as compared with three GH78 α-L-Rha-ases. The α-L-mannosidase activity of SpRhaM showed pH dependence, with highest activity observed at pH 7.0. In summary, we have shown that α-L-Rha-ases also have α-L-mannosidase activity. Our findings will be useful in the identification and structural determination of α-L-mannose-containing polysaccharides from natural sources for use in the pharmaceutical and food industries. 相似文献
98.
Kevinsanny Saburo Okazaki Osamu Takakuwa Yuhei Ogawa Koichi Okita Yusuke Funakoshi Junichiro Yamabe Saburo Matsuoka Hisao Matsunaga 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(5):1203-1213
Tension‐compression fatigue tests were performed on two types of Ni‐based superalloy 718 with different microstructures in which small artificial defects of various sizes and shapes were introduced. The susceptibility of the fatigue strength to the defects varied significantly with the microstructure morphology, ie, a smaller grain size made the alloy more susceptible to defects. The fatigue limit as a small‐crack threshold was successfully predicted using the parameter model. The evaluation of the fatigue limit was classified into the following three stages depending on the defect size: (a) harmless defect regime, (b) small‐crack regime, and (c) large‐crack regime. Such a classification enabled comprehensive evaluation of the fatigue limit in a wide range of defect size, considering (a) defect size over a range of small crack to large crack and (b) characteristics of matrix represented by grain size and hardness. 相似文献
99.
A Yamamoto T Wataya K Hayakawa A Matsunaga M Nishimura M Miyazaki 《Canadian Metallurgical Quarterly》1997,15(9-10):1383-1387
A novel, non-modulated polarimeter called a polarized photometric detector (PPD) was previously described by the authors. The PPD enables the measurement of the optical rotation of chiral compounds as a change in absorbance by placing two linear polarizers on either side of a flow cell of a conventional photometric detector. The present study describes the optimization of the conditions of PPD for highly sensitive detection of saccharides. To maximize the light intensity, the light balancing filter and slit were removed from the detector (Shimadzu model SPD-10AV). These modifications resulted in an approximately 15-fold increase in the incident light intensity when the maximum current was applied to the lamp. When this intense light was transmitted through the polarizers, the signal intensity followed the theoretical equation for phase angles up to around 1 rad. If the energy of the transmitted light was less than 700 mV, however, the baseline noise was too great to determine the chiral analyte accurately. Setting the phase angle between two polarizers at 50 degrees and the detection wavelength at 400 nm provided the most suitable conditions. This detector was applicable for the determinations of oligosaccharides in foodstuffs separated by HPLC using gradient elution. 相似文献
100.
K Ito K Honjo T Fujita H Awaya T Matsumoto N Matsunaga 《Canadian Metallurgical Quarterly》1998,22(5):742-748
High-resolution contrast-enhanced dynamic MRI of the uterus can be performed with the combination of a phased-array multicoil and fast GE techniques. This technique can improve the ability to visualize normal anatomy of the uterus and periuterine tissues, including vascular structures and pelvic ligaments, and to detect pathologic processes of the uterus and determine their extent. 相似文献