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1.
Armand  Louis 《AI & Society》2020,35(1):257-262
AI & SOCIETY - This paper is addressed to recent theoretical discussions of the Anthropocene, in particular Bernard Stiegler’s Neganthropocene (Open Universities Press, 2018), which...  相似文献   
2.
Rechargeable alkali metal (i.e., lithium, sodium, potassium)-based batteries are considered as vital energy storage technologies in modern society. However, the traditional liquid electrolytes applied in alkali metal-based batteries mainly consist of thermally unstable salts and highly flammable organic solvents, which trigger numerous accidents related to fire, explosion, and leakage of toxic chemicals. Therefore, exploring non-flammable electrolytes is of paramount importance for achieving safe batteries. Although replacing traditional liquid electrolytes with all-solid-state electrolytes is the ultimate way to solve the above safety issues, developing non-flammable liquid electrolytes can more directly fulfill the current needs considering the low ionic conductivities and inferior interfacial properties of existing all-solid-state electrolytes. Moreover, the electrolyte leakage concern can be further resolved by gelling non-flammable liquid electrolytes to obtain quasi-solid electrolytes. Herein, a comprehensive review of the latest progress in emerging non-flammable liquid electrolytes, including non-flammable organic liquid electrolytes, aqueous electrolytes, and deep eutectic solvent-based electrolytes is provided, and systematically introduce their flame-retardant mechanisms and electrochemical behaviors in alkali metal-based batteries. Then, the gelation techniques for preparing quasi-solid electrolytes are also summarized. Finally, the remaining challenges and future perspectives are presented. It is anticipated that this review will promote a safety improvement of alkali metal-based batteries.  相似文献   
3.
In this work, we present the synthesis of cationic surfactants based on 1-aminoisoindole. The physico-chemical properties were studied by conductometry, tensiometry, dynamic light scattering and transmission electron microscopy in water and in formamide. The reactivity of these novel surfactants has been studied at concentrations below and above critical aggregation concentrations (CAC) and it was found that reactions can proceed in structured media without the addition of other catalysts.  相似文献   
4.
Abstract

Using a high power CW CO2 laser, the pyrolysis in a flow reactor of different hydrocarbons/oxidizer mixtures with/without sensitizer lead to soots containing weightable quantities of fullerenes which were identified by FTIR spectroscopy, high performance liquid chromatography (HPLC) and time-of-flight mass spectrometry. The C60 and C70 quantification was done by HPLC. The FTIR spectroscopy of toluene extracts from the soots and of exhaust gases allowed to discuss some aspects concerning the influence of sensitizer (SF6) addition as well as of the oxidiser (O2/N2O) on the fullerene production in laser pyrolysis of benzene-based mixtures.  相似文献   
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6.
This paper considers a number of problems in a pharmaceutical downstream supply chain under specific constraints related to pharmaceutical products (e.g., their expiry date and regulations) and to inventory control (e.g., low prices of products, gift products or prices near zero, shortages prohibited but excess inventory allowed). As traditional models of inventory control and replenishment cannot optimize the total cost of the system, it is very important to consider the transportation cost as well. In this paper, we take into account some of these constraints and propose two models for multi-product replenishment policies, namely centralized and decentralized models. We seek to identify the best quantity and period of replenishment of products for a joint optimization of inventory and transportation costs. The proposed models can be applied to a specific family of products with a stable demand and high turnover rate, low prices (or gift products for some of them), and without any shortage. These two models are compared and the global approach is illustrated by a numerical example taken from a real-case study.  相似文献   
7.
This paper presents an optimization study of an irreversible refrigeration absorption system based on a new thermo-ecological criterion. The considered objective function is the ecological coefficient of performance (ECOP). It takes into account the first and second law of thermodynamics and is defined as the cooling load per unit loss rate of availability. The ecological coefficient of performance has been expressed and maximized according to the temperatures of the working fluid in the main components of the system. The corresponding optimal temperatures and other optimum performance parameters have been derived analytically, and the effects of the internal irreversibility, the heat leakage coefficient and the source temperature ratio on the global and optimal performances are discussed. The results show that the maximum coefficient of performance (COP) and ecological coefficient of performance (ECOP) occurs for the same operating conditions.  相似文献   
8.
There is urgent action required for replacing LiPF6 as a solute for Li-ion batteries electrolytes. This salt, prone to highly Lewis acidic PF5 release and hydrolysis to HF is responsible for deleterious reaction on carbonate solvents, corrosion of electrode materials leading to safety problems then release to toxic chemicals. A major advantage of LiPF6 is that it passivates aluminium. Most attempts to replace LiPF6 with hydrolytically-stable salts have been unsuccessful because of Al corrosion.We present here two “Hückel” type salts, namely lithium (2-fluoroalkyl-4,5-dicyano-imidazolate); fluoroalkyle = CF3 (TDI), C2F5 (PDI) with high charge delocalization. These thermally stable salts give both appreciably conductive solutions in EC/DMC (>6 mS cm−1 at 20 °C) with a lower decrease with temperature than LiPF6. Non fluorinated lithium (4,5-dicyano-1,2,3-triazolate) is comparatively less than half as conductive. The lithium transference number T+ measured by PFG-NMR is also higher. Voltammetry scans with either platinum or aluminium electrodes show an oxidation wall at 4.6 V versus Li+:Li°. These two salts are thus the first examples of strictly covalent, non-corroding salts allowing 4+ V electrode material operation. This is demonstrated with experimental Li/LiMn2O4 cells as beyond the third cycles, the fade of the three electrolytes were quasi-identical, though LiPF6 had a sharper initial decrease.  相似文献   
9.
Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo-Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods. Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical (HM) behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional (mode I) and shear fractures (modes II and III) induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts.  相似文献   
10.
Biogas produced from anaerobic fermentation of organic substances represents an alternative renewable energy source. Its utilization would contribute to substantial reduction of the solid waste volume in land-filling and incineration. Biogas so produced could be utilized on site or it could be injected into the natural gas distribution network. Microbiological and chemical compositions of different biogas types were determined in order to conduct qualitative and quantitative risk assessments of the potential health hazards associated with biogas use for cooking. Biogas types that could be allowed for injection in the natural gas pipelines were listed with recommendations, while outlining the European biogas injection policy. Results indicated that the injection of the processed biogas in the distribution network did not present any additional chemical or microbiological risk to consumers when compared to natural gas, provided that the biogas resulted from the fermentation of non-dangerous waste. However, since this study did not examine the microbiological and chemical composition of biogas originating from wastewater sludges and/or industrial wastes, the injection of this type of biogas into the gas distribution network should not be allowed unless a similar risk evaluation study is conducted for each case.  相似文献   
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