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991.
K. L. Mikolajczak M. O. Bagby I. A. Wolff 《Journal of the American Oil Chemists' Society》1965,42(3):243-245
Methyl crepenynate (methyl-cis-9-octadecen-12-ynoate) is readily isomerized by potassium hydroxide in ethylene glycol to an 8,10,12-octadecatrienoic acid
in good yield. A reaction carried out at 120C for 1 hr in 10% base is sufficient to convert the nonconjugated enyne system
completely to conjugated triene systems.
Presented at AOCS Meeting in New Orleans, 1964.
A laboratory of the No. Utiliz. Res. & Der. Div., ARS, USDA. 相似文献
992.
A series of statistical copolymers derived from 2‐(dimethylamino)ethyl methacrylate with four different hydrophobic comonomers (ethyl, butyl, cyclohexyl, and octyl methacrylates) have been prepared via conventional free radical copolymerization under bulk conditions. The copolymers have been subsequently modified, with 1,3‐propanesultone to yield the corresponding polysulfoproylbetaine derivatives. Those copolymers exhibiting the requisite aqueous solubility have been screened with respect to their antimicrobial activity against two common and notorious pathogens, namely Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). We show that certain copolymers do indeed exhibit antimicrobial activity. The extent of activity is related to the molecular characteristics of the materials such as the molar composition and structure of the hydrophobic comonomer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1036–1041, 2006 相似文献
993.
Capturing exposure sequences to compute high dynamic range (HDR) images causes motion blur in cases of camera movement. This also applies to light‐field cameras: frames rendered from multiple blurred HDR light‐field perspectives are also blurred. While the recording times of exposure sequences cannot be reduced for a single‐sensor camera, we demonstrate how this can be achieved for a camera array. Thus, we decrease capturing time and reduce motion blur for HDR light‐field video recording. Applying a spatio‐temporal exposure pattern while capturing frames with a camera array reduces the overall recording time and enables the estimation of camera movement within one light‐field video frame. By estimating depth maps and local point spread functions (PSFs) from multiple perspectives with the same exposure, regional motion deblurring can be supported. Missing exposures at various perspectives are then interpolated. 相似文献
994.
Kaiyu Zhao Matthew O. Ward Elke A. Rundensteiner Huong N. Higgins 《Computer Graphics Forum》2014,33(3):331-340
Linear models are commonly used to identify trends in data. While it is an easy task to build linear models using pre‐selected variables, it is challenging to select the best variables from a large number of alternatives. Most metrics for selecting variables are global in nature, and thus not useful for identifying local patterns. In this work, we present an integrated framework with visual representations that allows the user to incrementally build and verify models in three model spaces that support local pattern discovery and summarization: model complementarity, model diversity, and model representivity. Visual representations are designed and implemented for each of the model spaces. Our visualizations enable the discovery of complementary variables, i.e., those that perform well in modeling different subsets of data points. They also support the isolation of local models based on a diversity measure. Furthermore, the system integrates a hierarchical representation to identify the outlier local trends and the local trends that share similar directions in the model space. A case study on financial risk analysis is discussed, followed by a user study. 相似文献
995.
We address the problem of robust and efficient treatment of element collapse and inversion in corotational FEM simulations of deformable objects in two and three dimensions, and show that existing degeneration treatment methods have previously unreported flaws that seriously threaten robustness and physical plausibility in interactive applications. We propose a new method that avoids such flaws, yields faster and smoother degeneration recovery and extends the range of well‐behaved degenerate configurations without adding significant complexity or computational cost to standard explicit and quasi‐implicit solvers. 相似文献
996.
We present a novel approach to recording and computing panorama light fields. In contrast to previous methods that estimate panorama light fields from focal stacks or naive multi‐perspective image stitching, our approach is the first that processes ray entries directly and does not require depth reconstruction or matching of image features. Arbitrarily complex scenes can therefore be captured while preserving correct occlusion boundaries, anisotropic reflections, refractions, and other light effects that go beyond diffuse reflections of Lambertian surfaces. 相似文献
997.
M. S. Gray N. V. Lovegren R. O. Feuge 《Journal of the American Oil Chemists' Society》1976,53(12):727-731
The polymorphic behavior of cocoa butter mixed with 2-oleodipalmitin (POP) or 2-elaidodipalmitin (PEP) was investigated with
a differential scanning calorimeter. Six mixtures of cocoa butter containing 10, 25, and 50% POP and 10, 25, and 50% PEP were
used. Each of the three cocoa butter-POP mixtures exhibited at least four polymorphic forms. The lowmelting form was obtained
by quick chilling; the intermediate, by tempering for several hours just below the melting range; and the high-melting, by
raising the temperature slowly to 25 C then holding there overnight or longer. In the cocoa butter-POP mixtures, only the
low-melting form appeared to be more stable than the corresponding form for pure POP or cocoa butter. In addition to increased
stability of the unstable low form, the rate of conversion from the intermediate to the high form, normally quite slow, increased
in the cocoa butter-POP mixtures. Typical melting point lowering occurred when POP was added. POP was quite compatible with
cocoa butter, the tempered mixture melting as a single compound; and the melting curves were fairly sharp. The three cocoa
butter-PEP mixtures appeared to be incompatible. The cocoa butter and PEP behaved like a mixture of two fats, each of which
melted independently.
Presented at the AOCS Meeting, Chicago, Sept. 1973. 相似文献
998.
999.
Standard methods for the determination of iodine values of oils involve direct addition of halogen elements to the double bond. Since the reaction proceeds slowly there is a risk of substitution. A direct coulometrical titration method has been investigated. 相似文献
1000.
O. K. Chung Y. Pomeranz K. F. Finney M. P. Shogren 《Journal of the American Oil Chemists' Society》1978,55(9):635-641
Petroleum ether (PE) extracted 1.00% total free lipids (0.70% nonpolar and 0.30% polar) and 2-propanol (PrOH) extracted 1.36%
total free and bound lipids (0.73% nonpolar and 0.63% polar) from wheat flour; the lipid fractions were characterized by thin
layer chromatography. PE- or PrOH-defatted flours were baked after reconstitution with total, nonpolar, or polar wheat flour
lipids; or with equivalent amounts of nonionic sucrose monopalmitate (SMP), ethoxylated monoglycerides (EMG) — each with a
hydrophile-lipophile balance (HLB) of 14.0 or anionic sodium stearoyl-2-lactylate (SSL) — with an HLB value of 9.0. Defatted
flours supplemented with surfactants alone or in combination with wheat flour lipids were used in bread with no-shortening
and with 3%-shortening. The importance of the polar flour lipids in breadmaking was verified. The lipids in wheat flour were
essential for maximizing the beneficial effects of shortening on breadmaking quality. Nonionic SMP or EMG completely replaced
both PE-extractable wheat flour free total lipids ( or their non-polar or polar fractions) and 3% shortening; nonionic surfactants
with high HLB were better than the anionic SSL for replacing free flour lipids. No surfactant completely replaced unfractionated
PrOH-extracted lipids (free + bound) and shortening or total polar flour lipids (free + bound). All surfactants, especially
anionic SSL, added with PrOH-extracted polar lipids improved the overall bread-making properties of the PrOH-defatted flour
both in the absence and in the presence of shortening.
Presented at the AOCS Meeting, New York, May 1977 相似文献