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A.Varada Rajulu G. Babu Rao B. Ravi Prasad Rao A. Madhu Sudana Reddy Jiasong He Jun Zhang 《应用聚合物科学杂志》2002,84(12):2216-2221
Studies on some properties such as the density, the degradation temperatures, the morphology and the spectral features of the ligno‐cellulose fiber Hildegardia were carried out in both untreated and alkali treated form. The fibers are found to have good morphology and moderate initial and final degradation temperatures. On alkali treatment, the lignin was found to be eliminated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2216–2221, 2002 相似文献
3.
A classical ionic inorganic complex Na2[Cu(mnt)2] (mnt2− = maleonitriledithiolate = 1,2-dicyanoethylenedithiolate), that acts as a template in assembling neutral [Cu(salen)] (salen = bis(salicylidene)ethylenediamine) complexes forming a framework type arrangement, is accommodated in the channel formed in the crystal structure of a new type of host–guest compound [Cu(salen)]4 · Na2[Cu(mnt)2] (1). The non-covalent supramolecular interactions among [Cu(salen)] complexes and between [Cu(salen)] and [Cu(mnt)2]2− complexes in the crystal lattice of 1 result in weak antiferromagnetic coupling. 相似文献
4.
A basic goal in property testing is to identify a minimal set of features that make a property testable. For the case when the property to be tested is membership in a binary linear error-correcting code, Alon et al. (Trans Inf Theory, 51(11):4032–4039, 2005) had conjectured that the presence of a single low-weight codeword in the dual, and “2-transitivity” of the code (i.e., the code being invariant under a 2-transitive group of permutations on the coordinates of the code) suffice to get local testability. We refute this conjecture by giving a family of error-correcting codes where the coordinates of the codewords form a large field of characteristic two, and the code is invariant under affine transformations of the domain. This class of properties was introduced by Kaufman & Sudan (STOC, 2008) as a setting where many results in algebraic property testing generalize. Our result shows a complementary virtue: This family also can be useful in producing counterexamples to natural conjectures. 相似文献
5.
Conjugated linoleic acid, a fatty acid found in milk fat and ruminant meat is one of the functional food components. Modifying fatty acid composition so as to increase CLA and other beneficial PUFA/MUFA level and reducing SFA levels might be a key to enhance the neutraceutical and therapeutic value of ruminant-derived food products. In the present experiment, the effect of supplementation of polyphenol rich Terminalia chebula plant extract at different concentrations (1.06 g/kg and 3.18 g/kg of body weight in T1 and T2 groups, respectively) was investigated on fatty acid composition of rumen fluid, plasma, intramuscular fat and Δ9-desaturase activity in longissimus dorsi muscle of crossbred kids. Total MUFA and PUFA content in muscle were enhanced by 25 and 35%, respectively, whereas SFA was reduced by 20% thereby improving the desaturation index. Δ9-desaturase activity also increased by 47% resulting in an enhancement of total CLA content (58.73%) in muscle. 相似文献
6.
Madhu K. Shankarapani Subbu Ramamoorthy Ram S. Movva Srinivas Mukkamala 《Journal in Computer Virology》2011,7(2):107-119
One of the major problems concerning information assurance is malicious code. To evade detection, malware has also been encrypted
or obfuscated to produce variants that continue to plague properly defended and patched networks with zero day exploits. With
malware and malware authors using obfuscation techniques to generate automated polymorphic and metamorphic versions, anti-virus
software must always keep up with their samples and create a signature that can recognize the new variants. Creating a signature
for each variant in a timely fashion is a problem that anti-virus companies face all the time. In this paper we present detection
algorithms that can help the anti-virus community to ensure a variant of a known malware can still be detected without the
need of creating a signature; a similarity analysis (based on specific quantitative measures) is performed to produce a matrix
of similarity scores that can be utilized to determine the likelihood that a piece of code under inspection contains a particular
malware. Two general malware detection methods presented in this paper are: Static Analyzer for Vicious Executables (SAVE)
and Malware Examiner using Disassembled Code (MEDiC). MEDiC uses assembly calls for analysis and SAVE uses API calls (Static
API call sequence and Static API call set) for analysis. We show where Assembly can be superior to API calls in that it allows
a more detailed comparison of executables. API calls, on the other hand, can be superior to Assembly for its speed and its
smaller signature. Our two proposed techniques are implemented in SAVE) and MEDiC. We present experimental results that indicate
that both of our proposed techniques can provide a better detection performance against obfuscated malware. We also found
a few false positives, such as those programs that use network functions (e.g. PuTTY) and encrypted programs (no API calls
or assembly functions are found in the source code) when the thresholds are set 50% similarity measure. However, these false
positives can be minimized, for example by changing the threshold value to 70% that determines whether a program falls in
the malicious category or not. 相似文献
7.
8.
One‐Pot Lipase Entrapment Within Silica Particles to Prepare a Stable and Reusable Biocatalyst for Transesterification 下载免费PDF全文
In order to enhance the reusability, Rhizomucor miehei lipase was entrapped in a single step within silica particles having an oleic acid core (RML@SiO2). Characterization of RML@SiO2 by scanning and transmission electron microscopy and Fourier transform infrared studies supported the lipase immobilization within silica particles. The immobilized enzyme was employed for transesterification of cottonseed oil with methanol and ethanol. Under the optimum reaction conditions of a methanol‐to‐oil molar ratio of 12:1 or ethanol‐to‐oil molar ratio of 15:1, stirring speed of 250 revolutions/min (flask radius = 3 cm), reaction temperature of 40 °C, and biocatalyst concentration of 5 wt% (with respect to oil), more than 98 % alkyl ester yield was achieved in 16 and 24 h of reaction duration in case of methanolysis and ethanolysis, respectively. The immobilized enzyme did not require any buffer solution or organic solvent for optimum activity; hence, the produced biodiesel and glycerol were free from metal ion or organic molecule contamination. The activation energies for the immobilized enzyme‐catalyzed ethanolysis and methanolysis were found to be 34.9 ± 1.6 and 19.7 ± 1.8 kJ mol?1, respectively. The immobilized enzyme was recovered from the reaction mixture and reused in 12 successive runs without significant loss of activity. Additionally, RML@SiO2 demonstrated better reusability as well as stability in comparison to the native enzyme as the former did not lose the activity even upon storage at room temperature (25–30 °C) over an 8‐month period. 相似文献
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10.
Madhu Ramesh Dr. Pushparathinam Gopinath Prof. Thimmaiah Govindaraju 《Chembiochem : a European journal of chemical biology》2020,21(8):1052-1079
The global burden of Alzheimer's disease (AD) is growing. Valiant efforts to develop clinical candidates for treatment have continuously met with failure. Currently available palliative treatments are temporary and there is a constant need to search for reliable disease pathways, biomarkers and drug targets for developing diagnostic and therapeutic tools to address the unmet medical needs of AD. Challenges in drug-discovery efforts raise further questions about the strategies of current conventional diagnosis; drug design; and understanding of disease pathways, biomarkers and targets. In this context, post-translational modifications (PTMs) regulate protein trafficking, function and degradation, and their in-depth study plays a significant role in the identification of novel biomarkers and drug targets. Aberrant PTMs of disease-relevant proteins could trigger pathological pathways, leading to disease progression. Advancements in proteomics enable the generation of patterns or signatures of such modifications, and thus, provide a versatile platform to develop biomarkers based on PTMs. In addition, understanding and targeting the aberrant PTMs of various proteins provide viable avenues for addressing AD drug-discovery challenges. This review highlights numerous PTMs of proteins relevant to AD and provides an overview of their adverse effects on the protein structure, function and aggregation propensity that contribute to the disease pathology. A critical discussion offers suggestions of methods to develop PTM signatures and interfere with aberrant PTMs to develop viable diagnostic and therapeutic interventions in AD. 相似文献