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1.
Burnishing avoids the need for super finishing operations after the conventional turning process, to enhance the surface quality. This paper deals with the surface modifications of Al(B4C)p Metal Matrix Composites (MMC) workpiece material after burnishing with a TiAlN coated WC roller. The burnishing speed, lubrication type, burnishing passes, and coating were the input parameters. Surface hardness and roughness after the burnishing were studied. It was found that the coating on the WC roller had enhanced the hardness in the workpiece after burnishing in the case of Al-5?wt.% (B4C)p, under all conditions. The effect of the coating on the work piece surface hardness was not significant with Al-10?wt.% (B4C)p. While burnishing Al-5?wt.% (B4C)p, the minimum surface roughness combined with maximum surface hardness was obtained, during the third pass under dry condition using uncoated rollers. The number of passes to achieve the desired surface conditions reduced, on using coated rollers with kerosene as the lubricant.  相似文献   
2.
A facile microwave‐assisted one‐pot synthesis of sodium carboxymethylagarose and calcium carboxymethylagarose from Gracilaria dura agarose (Ag) has been described. The process is user friendly, and the highest degree of substitution was obtained within 15 min compared with the conventional method, which requires more than 3 h. Solubility and gelling behavior of the modified Ag products were found to be dependent on degree of substitution of the products. The characterizations were done by using Fourier transform infrared spectroscopy, 1H‐ and 13C‐nuclear magnetic resonance spectroscopy, thermogravimetric analysis, scanning electron microscopy, Inductively coupled plasma spectrophotometry (ICP), rheology, conductometer analysis, and DNA gel electrophoresis. These agarose derivatives were easily soluble in water and exhibited low thermal hysteresis, improved conductivity, and improved the DNA resolution ability of the parent G. dura Ag hydrogels. These hydrogels may have potential applications in the areas including electrochemical devices, microbiology, biomedical, and pharmaceuticals fields. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40630.  相似文献   
3.
Solid-state batteries enabled by solid-state polymer electrolytes (SPEs) are under active consideration for their promise as cost-effective platforms that simultaneously support high-energy and safe electrochemical energy storage. The limited oxidative stability and poor interfacial charge transport in conventional polymer electrolytes are well known, but difficult challenges must be addressed if high-voltage intercalating cathodes are to be used in such batteries. Here, ether-based electrolytes are in situ polymerized by a ring-opening reaction in the presence of aluminum fluoride (AlF3) to create SPEs inside LiNi0.6Co0.2 Mn0.2O2 (NCM) || Li batteries that are able to overcome both challenges. AlF3 plays a dual role as a Lewis acid catalyst and for the building of fluoridized cathode–electrolyte interphases, protecting both the electrolyte and aluminum current collector from degradation reactions. The solid-state NCM || Li metal batteries exhibit enhanced specific capacity of 153 mAh g−1 under high areal capacity of 3.0 mAh cm−2. This work offers an important pathway toward solid-state polymer electrolytes for high-voltage solid-state batteries.  相似文献   
4.
Recently, an innovative trend like cloud computing has progressed quickly in Information Technology. For a background of distributed networks, the extensive sprawl of internet resources on the Web and the increasing number of service providers helped cloud computing technologies grow into a substantial scaled Information Technology service model. The cloud computing environment extracts the execution details of services and systems from end-users and developers. Additionally, through the system’s virtualization accomplished using resource pooling, cloud computing resources become more accessible. The attempt to design and develop a solution that assures reliable and protected authentication and authorization service in such cloud environments is described in this paper. With the help of multi-agents, we attempt to represent Open-Identity (ID) design to find a solution that would offer trustworthy and secured authentication and authorization services to software services based on the cloud. This research aims to determine how authentication and authorization services were provided in an agreeable and preventive manner. Based on attack-oriented threat model security, the evaluation works. By considering security for both authentication and authorization systems, possible security threats are analyzed by the proposed security systems.  相似文献   
5.
Any part cannot be manufactured to the required nominal dimensions due to inherent variations in workmanship, material, and machine. The specification of tolerance on part dimensions plays a major role on performance, quality, and cost of the product. Distribution of tolerance among the components of an assembly is known as tolerance allocation. The selection of alternative processes for tolerance allocation also plays a vital role in reducing manufacturing cost. Near-optimal allocated tolerances are obtained using nontraditional optimization techniques in which the solutions are achieved randomly. Also, there is a chance for omitting the better process for allocation. The results of successive run of the program based on these techniques will not yield consistent results. An attempt has been made in this work to solve the above problem using Lagrange multiplier method for complex assemblies with univariate search method. The methodology has been demonstrated on wheel mounting assembly. The example product after implementing the proposed method would yield 1.4% savings in manufacturing cost as compared with the cost obtained by Singh.  相似文献   
6.
A simple calorimetric method for determination of amylose content in starch is reported. Starches were heated in the presence of two common surfactants, viz., sodium dodecyl sulphate (SDS) and cetyltrimethylammonium bromide (CTAB), and the enthalpies of melting of the amylose‐surfactant complexes were determined using Modulated Differential Scanning Calorimetry (MDSC). A large number of native starches including cereal, root and pea starches were examined. The results were compared with those obtained by iodimetry and gel permeation chromatography (GPC) for all the starches. There was a good correlation between the values from iodimetry and GPC with those obtained using the surfactants. Both surfactants seemed to work equally well, even for those starches with about 40% amylose content. However, in case of SDS higher standard deviations were usually obtained than for CTAB in the determination of transition enthalpies.  相似文献   
7.
Six different lithium bismuth boro-tungstate glasses with chemical composition 20Li2O-(20-x)Bi2O3-xWO3-60B2O3 (x = 0, 1, 2, 3, 4 and 5 mol%) were produced by the quenching method. Then, the glasses were investigated by means of their optical, mechanical, chemical durability and gamma ray shielding properties. Measured values of density and ultrasonic velocities were used to determine the elastic properties of the glasses. The optical band gap determined using the absorbance spectrum fitting (ASF) model was found to decrease under Bi2O3/WO3 substitution. The presence of BO3, BO4, BiO6, and WO4 structural groups in the glasses was confirmed by Fourier transform infrared spectroscopy (FTIR). The dissolution rate in the glass 20Li2O–15Bi2O3–5WO3–60B2O3 (LBWB5) was found to be 10 times lower than 20Li2O-20Bi2O3– 60B2O3. Mass attenuation coefficients (MAC) values of the produced glasses were determined using the MCNPX Monte Carlo code and Phy-X/PSD program. The photon attenuation parameters such as half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF) and energy absorption buildup factor (EABF) were also studied. The obtained results showed that Bi2O3/WO3 substitution has a direct impact on the photon attenuation abilities of produced glasses. More specifically, HVL values increased from 0.252 × 10?2 cm for LBWB0 glass to 0.275 × 10?2 cm for LBWB5 glass. However, different trends were observed for the photon buildup factors for the produced glasses. It can be concluded that the produced glasses have promising structural, optical, and photon attenuation properties to be used for gamma shielding applications.  相似文献   
8.
These days, peoples are more concerned respects petroleum product energy and conservational issues caused on the power generation networks and renewable power resources at any other time. Amongst the renewable power resources, solar and windmill power generations are essential competitors. Photovoltaic modules additionally have moderately least transformation effectiveness. General system price was decreased utilizing significant productivity control which are made to determine for most significant achievable energy from solar PV array module utilizing MPPT procedures. Existing solar power generation likewise have the burden of being for the day outputs is less immediate introduction from natural sun radiation. By utilizing the Internet of Things (IoT) strategies for monitoring and controlling the solar power generation was significantly enhance the performance, and maintenance of the solar power plant. In this work explicitly argue advances IoT technique to increase output result of solar power generation at the system level. Covering turning the photovoltaic system in the position of maximum sunlight, obtaining significant available power obtained from the solar PV array and significant battery health management by using sophisticated distribution control (SDC) and independent component analysis techniques (ICA).The simulation work done under with the MATLAB software using proposed SDC and ICA logics the simulation results demonstrate the efficiency of the proposed method and its ability to track the maximum power of the PV panel. Over 97% efficiency achieved by using SDC and ICA methods.  相似文献   
9.
The Internet of Things (IoT) is the all-around trusted technology that associates natural objects to the web for giving straightforwardness and different functionalities and the hybrid power system has characterized as the power grid incorporated with an extensive network. With the change in innovation and developments needs to tackle the energy crises by utilizing hybrid renewable energy resources. The failure of electrical power in remote territories drives associations to investigate elective arrangements, for example, renewable energy power systems. The energy created by hybrid renewable energy sources are dependent on the variation and load demand, such a renewable power system must be equipped for fulfilling the necessities whenever and store the extra power for usage in deficiency situations. An independent renewable energy network to meet the coveted electric load with some sources, little excess power and minimal cost of energy. The essential goal of the design criteria is to limit the entire cost which incorporates initial, operational and support cost. In this work life-cycle cost (LCC), loss of load probability (LOLP) and loss of power supply probability (LPSP) have considered as the genuine factors and a Generous Transformational Optimization Algorithm (GTOA) has projected to pick the greatest possible configuration of a hybrid power framework. Internet of Things (IoT) conveyed in crossover control framework and gave a valuable proposition about assorted advances and norms of a renewable power source, and it additionally gives a review of a few applications and driving variables of a hybrid control framework. Simulation work done with MATLAB software and result helps the efficiency of the proposed technique and confirm that it is 97% efficiency than other ordinary strategies.  相似文献   
10.
A miniature sun photometer has been developed that makes continuous almucantar scans to measure solar irradiance and sky radiance in four wavelength bands set by interference filters. It has a well-defined field of view and can rapidly compensate for a tilting platform. It weighs less than 400 g and has an average power consumption of less than 5 W. Together, these characteristics make it suitable for vertical profiles using small balloons or unmanned aircraft systems (UASs). Preliminary results are presented showing measurements of optical depth and the phase function of scattered sunlight. An optical depth of about 0.03 in a clean boundary layer was measurable with an accuracy of better than 0.01.

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