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71.
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Porous Electrospun Fibers with Self‐Sealing Functionality: An Enabling Strategy for Trapping Biomacromolecules 下载免费PDF全文
Jin Zhang Ting Zheng Emine Alarçin Batzaya Byambaa Xiaofei Guan Jianxun Ding Yu Shrike Zhang Zhongming Li 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(47)
Stimuli‐responsive porous polymer materials have promising biomedical application due to their ability to trap and release biomacromolecules. In this work, a class of highly porous electrospun fibers is designed using polylactide as the polymer matrix and poly(ethylene oxide) as a porogen. Carbon nanotubes (CNTs) with different concentrations are further impregnated onto the fibers to achieve self‐sealing functionality induced by photothermal conversion upon light irradiation. The fibers with 0.4 mg mL?1 of CNTs exhibit the optimum encapsulation efficiency of model biomacromolecules such as dextran, bovine serum albumin, and nucleic acids, although their photothermal conversion ability is slightly lower than the fibers with 0.8 mg mL?1 of CNTs. Interestingly, reversible reopening of the surface pores is accomplished with the degradation of PLA, affording a further possibility for sustained release of biomacromolecules after encapsulation. Effects of CNT loading on fiber morphology, structure, thermal/mechanical properties, degradation, and cell viability are also investigated. This novel class of porous electrospun fibers with self‐sealing capability has great potential to serve as an enabling strategy for trapping/release of biomacromolecules with promising applications in, for example, preventing inflammatory diseases by scavenging cytokines from interstitial body fluids. 相似文献
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In this study, the phenol adsorption capacity of cetyltrimethylammonium bromide modified clays (MMT-CTAB) and cetyltrimethylammonium bromide modified pulp tea (WPT-CTAB) were studied. In batch adsorption experiments performed with MMT-CTAB, the effects of parameters such contact time, phenol concentration, pH of solution and adsorbent dosage were investigated. The effect of temperature on phenol adsorption onto MMT-CTAB and WPT-CTAB was examined; equilibrium and thermodynamic studies were completed. The highest phenol removal was found at pH 4.0 for MMT-CTAB and WPT-CTAB. To analyze the kinetics of phenol adsorption onto MMT-CTAB, the pseudo first-order and pseudo second-order kinetic models were applied. The kinetic data fitted better to the pseudo second-order model than the pseudo first-order kinetic model for MMT-CTAB. The characterization of adsorbents in phenol adsorption was clarified with the FTIR technique. Thermodynamic parameters such as ΔH°, ΔS° and ΔG° were calculated for each adsorption process. The adsorption process was found to be exothermic and spontaneous for phenol adsorption by MMT-CTAB and WPT-CTAB. The results were analyzed with the Langmuir, Freundlich, Temkin and Harkins–Jura equations using linearized correlation coefficients at different temperatures. The Langmuir equation was found to best represent the equilibrium data for phenol adsorption onto MMT-CTAB and WPT-CTAB. 相似文献
74.
Breast cancer detection using K‐nearest neighbors data mining method obtained from the bow‐tie antenna dataset 下载免费PDF全文
Breast cancer, has been a significant cancer type for women on the society. Early diagnosis and timely medical treatment are important key factors spreading to the other tissues and permitting long‐time survival of patients. Since the existing methods have several serious shortfalls, microwave imaging method for the diagnosis of early stage tumors has been interested by different scientific research groups in terms of moderating endogenous the electrical property difference between healthy tissue and malignancies. In this article, both an ultra‐wideband bow‐tie antenna with enhanced bandwidth and a 3D breast model which has different electrical properties which are permittivity and conductivity is created in simulation tool to solve electromagnetic field values. Return loss, VSWR, and radiation pattern characteristics, which are significant antenna parameters, are simulated and obtained whether the antenna possess an efficient characteristic or not. Electric field values over the breast tissue in which there is a tumor or not tumor are evaluated. In this article, above‐mentioned values of frequency bandwidth, dielectric constant of antenna's substrate, electric field, and tumor information were consisted in their dataset. This dataset obtained from the Bow‐Tie Antenna was used to detect the breast cancer with one of the data mining method, which is K‐Nearest Neighbor Algorithm. 相似文献
75.
Estimating average precision when judgments are incomplete 总被引:2,自引:1,他引:1
We consider the problem of evaluating retrieval systems with incomplete relevance judgments. Recently, Buckley and Voorhees
showed that standard measures of retrieval performance are not robust to incomplete judgments, and they proposed a new measure,
bpref, that is much more robust to incomplete judgments. Although bpref is highly correlated with average precision when the judgments
are effectively complete, the value of bpref deviates from average precision and from its own value as the judgment set degrades,
especially at very low levels of assessment. In this work, we propose three new evaluation measures induced AP, subcollection AP, and inferred AP that are equivalent to average precision when the relevance judgments are complete and that are statistical estimates of average precision when relevance judgments are a random subset of complete judgments. We consider natural scenarios which
yield highly incomplete judgments such as random judgment sets or very shallow depth pools. We compare and contrast the robustness
of the three measures proposed in this work with bpref for both of these scenarios. Through the use of TREC data, we demonstrate
that these measures are more robust to incomplete relevance judgments than bpref, both in terms of how well the measures estimate
average precision (as measured with complete relevance judgments) and how well they estimate themselves (as measured with
complete relevance judgments). Finally, since inferred AP is the most accurate approximation to average precision and the
most robust measure in the presence of incomplete judgments, we provide a detailed analysis of this measure, both in terms
of its behavior in theory and its implementation in practice.
We gratefully acknowledge the support provided by NSF grants CCF-0418390 and IIS-0534482. 相似文献
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The hydrodynamics of an up-flow three phase packed bed bioreactor were investigated experimentally using tracer techniques. The effects of the liquid and gas velocities, and the particle size on the Peclet number (Pe) and on the liquid hold-up (εL) were determined. While the range of gas and liquid flow rate were chosen according to biotic conditions. It was found that the Pe was not influenced from liquid flow rate, however decreased with increasing gas flow rate and particle/reactor diameter ratio (dp/Dc). Also, it was found that liquid hold-up was not influenced from gas flow rate, however increased with increasing liquid flow rate and decreased with increasing dp/Dc ratio. The correlation which connected the Bodenstein number to gas phase particle Reynolds number and dp/Dc ratio and the correlation which connected the liquid hold-up, liquid phase particle Reynolds number and dp/Dc ratio were found using Marquardt-Levenberg approach. 相似文献
80.
Josephine Q.N. Nguyen Wojtek Drabarek Serdar Yavuzyigitoglu Eva Medico Salsench Robert M. Verdijk Nicole C. Naus Annelies de Klein Emine Kili Erwin Brosens 《International journal of molecular sciences》2020,21(24)
Uveal melanoma (UM) is the most common primary intraocular malignancy of the eye. It has a high metastatic potential and mainly spreads to the liver. Genetics play a vital role in tumor classification and prognostication of UM metastatic disease. One of the driver genes mutated in metastasized UM is subunit 1 of splicing factor 3b (SF3B1), a component of the spliceosome complex. Recurrent mutations in components of the spliceosome complex are observed in UM and other malignancies, suggesting an important role in tumorigenesis. SF3B1 is the most common mutated spliceosome gene and in UM it is associated with late-onset metastasis. This review summarizes the genetic and epigenetic insights of spliceosome mutations in UM. They form a distinct subgroup of UM and have similarities with other spliceosome mutated malignancies. 相似文献