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81.
Spandex is increasingly used in either every course or alternating courses of knitted fabrics to impart a greater level of stretch and form stability than that can be achieved with cotton alone. The incorporation of spandex to the fabric structure effects many of the fabric properties. In this study, 100% cotton, half-plated and full-plated, plain and rib fabrics which are very commonly used in underwear and outerwear clothing are investigated for physical, dimensional, geometrical, and some comfort properties and compared to each other. Several conclusions could be obtained such as the wicking heights of the plain fabrics were higher than those of the 1×1 rib fabrics. Transfer wicking ratios of the half-plated fabrics were the highest, whereas the transfer wicking ratios of the full-plated fabrics were the lowest. Extension under constant load and residual deformation ratios decreased with the addition of spandex and the increase in spandex content. Plain fabrics generally performed better than 1×1 rib fabrics in terms of residual deformation ratios.  相似文献   
82.
The treatment of synthetic acid mine drainage (AMD) water (pH 3.0-6.5) containing sulfate (3.0-3.5 g L(-1)) and various metals (Co, Cu, Fe, Mn, Ni, and Zn) was studied in an ethanol-fed sulfate-reducing 4-compartment anaerobic baffled reactor (ABR) at 32°C. The reactor was operated for 160 days at different chemical oxygen demand (COD)/sulfate ratios, hydraulic retention times (HRT), pH, and metal concentrations to study the robustness of the process. The last compartment of the reactor was aerated at different rates to study the bio-oxidation of sulfide to elemental sulfur. The highest sulfate reduction efficiency (88%) was obtained with a feed sulfate concentration of 3.5 g L(-1), COD/sulfate mass ratio of 0.737, feed pH of 3.0 and HRT of 2 days without aeration in the 4th compartment. The corresponding COD removal efficiency was about 92%. The alkalinity produced in the sulfidogenic ethanol oxidation neutralized the acidic mine water from pH 3.0-4.5 to pH 7.0-8.0. Effluent soluble and total heavy metal concentrations were substantially reduced with removal efficiencies generally higher than 99%, except for Mn (25-77%). Limited aeration in the 4th compartment of ABR promoted incomplete oxidation of sulfide to elemental sulfur rather than complete oxidation to sulfate. Depending on the aeration rate and HRT, 32-74% of produced sulfide was oxidized to elemental sulfur. This study demonstrates that by optimizing operating conditions, sulfate reduction, metal removal, alkalinity generation, and excess sulfide oxidation can be achieved in a single ABR treating AMD.  相似文献   
83.
A. Ucar  M. Inalli 《Renewable Energy》2005,30(7):1005-1019
Thermal performance and economic feasibility of two types of central solar heating system with seasonal storage under four climatically different Turkey locations are investigated. The effects of storage volume and collector area on the thermal performance and cost are studied for three load sizes. The simulation model of the system consisting of flat plate solar collectors, a heat pump, under ground storage tank and heating load based on a finite element analysis and finite element code ANSYS™ is chosen as a convenient tool. In this study, the lowest solar fraction value for Trabzon (41°N) and the highest solar fraction value for Adana (37°N) are obtained. Based on the economic analysis, the payback period of system is found to be about 25–35 years for Turkey.  相似文献   
84.
Ucar  N.  Ekinci  C.  Calik  A.  Keddam  M. 《Metal Science and Heat Treatment》2022,64(3-4):176-182
Metal Science and Heat Treatment - The kinetics of boriding of Fe – Ni alloys containing 60, 70, 80, and 90 wt.% Ni at 1073 – 1373 K for 2 – 8 h in powdered mixtures with the use...  相似文献   
85.
86.
Arsenic removal from drinking water was investigated using electrocoagulation (EC) followed by filtration. A sand filter was used to remove flocs generated in the EC process. Experiments were performed in a batch electrochemical reactor using iron electrodes with monopolar parallel electrode connection mode to assess their efficiency. The effects of several operating parameters on arsenic removal such as current density (1.5–9.0 mA cm?2), initial arsenic concentration (50–500 μg L?1), operating time (0–15 min), electrode surface area (266–665 cm2), and sodium chloride concentrations (0.01 and 0.02M) were examined. The EC process was able to decrease the residual arsenic concentration to less than 10 μg L?1. Optimum operating conditions were determined as an operating time of 5 min and current density of 4.5 mA cm?2 at pH of 7. The optimum electrode surface area for arsenic removal was found to be 266 cm2 taking into consideration cost effectiveness. The residual iron concentration increased with increasing residence time, and maximum residual iron value was measured as 287 μg L?1 for electrode surface area of 266 cm2. The addition of sodium chloride had no significant effect on residual arsenic concentration, but an increase in current density was observed.  相似文献   
87.
Healthcare Systems and Other Applications   总被引:1,自引:0,他引:1  
This paper presents healthcare systems and their applications namely helping people with dementia navigate their day, empowering the elderly and the cognitively disabled, context awareness in residence for elders, RFID-based nutritional assistance, a computer-based library for the blind, an NLP-based tool for assisting people with autism, making smart clothing smarter, PAS: a wireless-enabled personal assistance system for independent living  相似文献   
88.
Energy and exergy analyses of a raw mill in a cement production   总被引:2,自引:0,他引:2  
Cement production has been one of the most energy intensive industries in the world. In order to produce raw materials preparation, clinker and rotary kilns are widely used in cement plants. The objective of this study is to perform energy and exergy analysis of a raw mill (RM) and raw materials preparation unit in a cement plant in Turkey using the actual operational data. The RM has a capacity of 82.9 ton-material hourly. Both energy and exergy efficiencies of the RM are investigated for the plant performance analysis and improvement, and are determined to be 84.3% and 25.2%, respectively. The present technique is proposed as a useful tool in the analysis of energy and exergy utilization, developing energy policies and providing energy conservation measures.  相似文献   
89.
In this study, the effects of Ag, ZnO, and CuO nanoparticles (NPs) on the mechanical, thermal, and biodegradability properties of the compatibilized polyethylene (PE)/thermoplastic starch (TPS) blends were investigated. Polyethylene-grafted maleic anhydride (PE-g-MA) was used as the compatibilizer. The compatibilized PE/TPS blends with different NPs were prepared by melt mixing method in a laboratory scale extruder and then pressurized in the press machine. The use of ZnO NP together with the compatibilizer in PE/TPS-based films significantly increased the tensile stress values. The use of different type NPs did not cause any significant change in the thermal stability of PE/TPS-based films. However, the effects of NPs were observed on the TPS degradation steps. The prepared films with different NPs showed an antibacterial activity between 60% and 70%. The highest crystallinity value was obtained in Ag NP containing films, among others. According to scanning electron microscopy analysis, better distribution was observed for ZnO and Ag NPs than CuO NP. In general, it can be said that the addition of NPs to PE/TPS-based blends significantly reduces the partial biodegradability of the resulting films.  相似文献   
90.
The aim of this study is to identify the effects of force feedback haptic applications developed in virtual reality environments (VREs), which is an important field of study in computer science and engineering, on gifted students’ attitudes towards chemistry education in learning process. A 3D 6 DOF (Degree of Freedom) haptik device (Phantom Omni?) has been used to develop the algorithm in this study. It can be used to transmit force and motion using a haptic device. Visual C++ was choosen as the software development environment. OpenGL? and Haptic Device Application Programming Interface have been used for rendering graphics. At the 3D image creation state Wrap 1200?, which is a kind of head-mounted display, has been chosen. The sample of this study consists of 52 students identified as gifted and are attending 6th and 7th grades at the Istanbul Science &; Art Center in Istanbul. The experimental group studied chemical bonds using an application developed by using a force feedback haptic device in VRE and the control group studied it by traditional teaching methods. The study reveals that there is a relation between using force feedback haptic applications which are developed in VREs and gifted students’ attitudes towards educational programs.  相似文献   
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