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41.
Sulfide-based all-solid-state batteries (ASSBs) have been featured as promising alternatives to the current lithium-ion batteries (LIBs) mainly owing to their superior safety. Nevertheless, a solution-based scalable manufacturing scheme has not yet been established because of the incompatible polarity of the binder, solvent, and sulfide electrolyte during slurry preparation. This dilemma is overcome by subjecting the acrylate (co)polymeric binders to protection−deprotection chemistry. Protection by the tert-butyl group allows for homogeneous dispersion of the binder in the slurry based on a relatively less polar solvent, with subsequent heat-treatment during the drying process to cleave the tert-butyl group. This exposes the polar carboxylic acid groups, which are then able to engage in hydrogen bonding with the active cathode material, high-nickel layered oxide. Deprotection strengthens the electrode adhesion such that the strength equals that of commercial LIB electrodes, and the key electrochemical performance parameters are improved markedly in both half-cell and full-cell settings. The present study highlights the potential of sulfide-based ASSBs for scalable manufacturing and also provides insights that protection−deprotection chemistry can generally be used for various battery cells that suffer from polarity incompatibility among multiple electrode components.  相似文献   
42.
Despite their unparalleled theoretical capacity, lithium‐metal anodes suffer from well‐known indiscriminate dendrite growth and parasitic surface reactions. Conductive scaffolds with lithium uptake capacity are recently highlighted as promising lithium hosts, and carbon nanotubes (CNTs) are an ideal candidate for this purpose because of their capability of percolating a conductive network. However, CNT networks are prone to rupture easily due to a large tensile stress generated during lithium uptake–release cycles. Herein, CNT networks integrated with a polyrotaxane‐incorporated poly(acrylic acid) (PRPAA) binder via supramolecular interactions are reported, in which the ring‐sliding motion of the polyrotaxanes endows extraordinary stretchability and elasticity to the entire binder network. In comparison to a control sample with inelastic binder (i.e., poly(vinyl alcohol)), the CNT network with PRPAA binder can endure a large stress during repeated lithium uptake–release cycles, thereby enhancing the mechanical integrity of the corresponding electrode over battery cycling. As a result, the PRPAA‐incorporated CNT network exhibits substantially improved cyclability in lithium–copper asymmetric cells and full cells paired with olivine‐LiFePO4, indicating that high elasticity enabled by mechanically interlocked molecules such as polyrotaxanes can be a useful concept in advancing lithium‐metal batteries.  相似文献   
43.
Echinococcus granulosus and Echinococcus multilocularis cause liver hydatid disease. One of its most common complications is rupture into the bile ducts; however, penetration of a cyst into a vessel is a very rare complication. We detected a defect (2 x 1 cm) on the wall of the right hepatic vein, in addition to three distinctive ruptures into the bile ducts, in our case. For systemic hypotension due to a bleeding during operation and to repair the vessel wall defect, an urgent right thoracotomy followed by a radial phrenotomy was needed. We were able to reach the operation site easily and repaired the vessel wall with polypropylene suture. Because of the occurrence of these two complications together and the difficulties of the operation, we decided to report this case.  相似文献   
44.
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45.
In this study a comprehensive performance analysis of the Bigadic Geothermal District Heating System (GDHS) in Balikesir, Turkey is performed through thermodynamic assessment in terms of energy and exergy efficiencies. The actual thermal data taken from the Technical Department of the GDHS are utilized in the analysis to determine the exergy destructions in each component of the system and the overall energy and exergy efficiencies of the system for two reference temperatures taken as 15.6 °C for November (e.g., case 1) and 11 °C for December (e.g., case 2). The energy and exergy flow diagrams are clearly drawn to illustrate how much destructions/losses take place in addition to the inputs and outputs. The average energy and exergy efficiencies are found to be 30% and 36% for case 1, and 40% and 49% for case 2, respectively. The key reason as to why the exergy efficiencies are higher is because the heat recovery option is used through the reinjection processes which make use of waste heat. A parametric study is also conducted to show how energy and exergy flows change with the environment temperature. The results are expected to be helpful to researchers and engineers in the area.  相似文献   
46.
Yelda Coskun 《Polymer》2004,45(15):4989-4995
Terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester (TATE) was synthesized through the reaction of 2-thiophen-3-yl-ethanol and terepthaloyl chloride. Homopolymer of TATE was synthesized via potentiostatic and potentiodynamic methods by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in dichloromethane/borontrifluoride ethylether solvent mixture (DM/BFEE) (8:2, v/v). Copolymerisation of TATE with thiophene was achieved in DM/BFEE solvent mixture (8:2, v/v) by using TBAFB as the supporting electrolyte in the presence of thiophene. The chemical structure of monomer is characterised via NMR and FTIR. Both homopolymer (PTATE) and copolymer P(TATE-co-Th) were characterised by various techniques including cyclic voltammetry, FTIR, scanning electron microscopy and UV-VIS spectroscopy. Conductivities of samples were measured by four probe technique. Optoelectrochemical analysis indicates that the homopolymer and copolymer have an electronic band gap, measured as the onset of the π-to-π* transition, as 2.17 and 2.00 eV, respectively.  相似文献   
47.
Computer-aided prototyping evaluates and refines software requirements by defining requirements specifications, designing underlying compositional architecture, doing restricted real-time scheduling, and constructing a prototype by using reusable executable software components. This paper presents a case study of the Computer Assisted Resuscitation Algorithm (CARA) software for a casualty intravenous fluid infusion pump and explores the effectiveness of performing rapid prototyping with parallel conceptualization to expose requirements issues. Using a suite of prototyping tools, five different design model alternatives are generated based on the analysis of customer requirements documents. Further comparison is conducted with specific focus on a sample of comparative criteria: simplicity of design, safety aspects, requirements coverage, and enabling architecture. The case study demonstrates the usefulness of comparative rapid prototyping for revealing the omissions and discrepancies in the requirements document. The study also illustrates the efficiency of creating/modifying parallel models and reason for their complexity by using the tool suite. Additional enhancements for the prototyping suite are highlighted.  相似文献   
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49.
As part of a large‐scale programme to investigate the health effects of exposure to borate minerals in Turkey, boron concentrations in vegetables, fruits and some other foods were determined. From all borate‐producing regions of the country, 22 species of fruit, 17 species of vegetable, 12 species of cereal, legume and oilseed, three species of herbs and six types of other food were collected in 1999 and analysed for boron concentrations using the Azomethine H method. The results were compared with 37 types of food collected from areas well distant from the borate‐producing areas. The total number of samples evaluated was 420. Pistachio (67.0 mg kg?1) had the highest concentration of boron, followed by grape leaf (60.48 mg kg?1), sour cherry (57.03 mg kg?1), quince (38.78 mg kg?1), peach (34.49 mg kg?1), grape (20.70 mg kg?1), green beans (19.49 mg kg?1), unripe peach (18.92 mg kg?1) and parsley (10.24 mg kg?1) from the borate‐producing regions. A large number of foods contained boron at higher concentrations than those reported in the literature, most probably due to the high boron content of these Turkish soils. According to the results of t‐tests, the area itself does not have a significant effect (p > 0.05) on boron concentration in all foods evaluated so far. Copyright © 2003 Society of Chemical Industry  相似文献   
50.
OBJECTIVE: To determine the efficiency of in vitro maturation, expressed by nuclear maturation, of oocytes aspirated during gynecologic surgeries or collected from excised ovaries. To assess the effect of patient age and cycle phase at collection on the oocyte's ability to mature in vitro. To examine the time course of oocyte maturation in vitro. DESIGN: Nuclear maturation based on patient criteria compared. SETTING: University-based IVF program and research center. PATIENT(S): Consented patients undergoing gynecologic surgeries or patients undergoing oophorectomy. INTERVENTION(S): Oocytes were maintained in culture for 48 hours and evaluated for maturation. MAIN OUTCOME MEASURE(S): Nuclear maturation evaluated as germinal vesicle breakdown (GVBD) or progression to the metaphase II (MII) stage. RESULT(S): A significantly higher percentage of oocytes collected during the follicular phase of the menstrual cycle underwent GVBD than did oocytes collected during the luteal phase (60% versus 48%, respectively). The percentage of oocytes reaching the MII stage, from these two groups, was not different. No statistically significant differences in maturation were observed in oocytes from different ovarian sources or from patients >40 or <40 years of age. CONCLUSION(S): These data suggest that oocytes collected during the follicular phase are more likely to undergo GVBD than oocytes collected during the luteal phase. In this study, ovarian source, age, or cycle phase did not influence the final meiotic maturation of oocytes to metaphase II.  相似文献   
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