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151.
In this study, the effects of trans fatty acids (TFAs) on rheological properties of dough (elastic moduli (G’), loss moduli (G”), complex modulus (G*)) and textural properties of dough and cookie (hardness) were studied. Two different groups of fat samples having different TFA composition but similar solid fat content (SFC) were prepared. Samples of the first group (group 1) had TFA between 0.0 and 56.23 %, while the samples of the second group (group 2) contained trans isomers ranging from 0.0 to 44.40 %. Texture measurements of different doughs and cookies prepared with different fat samples were performed. Texture measurements indicated that hardness values of doughs increased from 3950 ± 420 to 5498 ± 506 g in group 1 and 4700 ± 501 to 6787 ± 369 g in group 2 with increased amounts of TFAs. A particularly high, almost three‐fold increase in complex modulus values was observed in the dough samples containing the highest TFA levels compared with samples containing 0.0 % TFA. Although not significantly different, mean hardness and relative sound intensity values of cookies displayed an initial decreasing trend and then both parameters had maximum values when the TFA content was at maximum in both groups.  相似文献   
152.
Porous ceramics offer unique properties that can bring advances to many application areas. The freeze-casting process has a strong potential for fabricating porous ceramics; however, the effects of process parameters on part porosity must be well understood for scalable manufacturing via freeze casting. This paper presents an experimental analysis of the freeze-casting process that correlates the freeze-casting parameters with pore characteristics. A full-factorial design of experiments is conducted on a unidirectional freeze-casting testbed using silica as the ceramic material and camphene as the solvent. The effects of solid loading, particle size, cooling temperature, and the distance from the cooling surface on porosity characteristics are evaluated. The fabricated samples are cross-sectioned vertically and horizontally and imaged using scanning electron microscopy. Image processing is used to obtain the porosity characteristics of areal porosity, pore size, pore shape, and pore orientation. The capability to steer the pore orientation is also demonstrated through bidirectional freezing experiments supported by a finite-element model. As a result, a quantitative understanding of the effects of freeze-casting process parameters on porosity characteristics is gained for the silica–camphene system. These results and the presented approach can be used for reproducible manufacture of porous ceramics with controlled porosity.  相似文献   
153.
Flame retardancy of poly(ethylene terephthalate), PET, was improved using different flame retardant additives such as triphenylphosphate, triphenylphosphine oxide, zinc borate, and boron phosphate (BP). Composites were prepared using a twin screw extruder and subsequently injection molded for characterization purposes. The flame retardancy of the composites was determined by the limiting oxygen index (LOI) test. Smoke emission during fire was also evaluated in terms of percent light transmittance. Thermal stability and tensile properties of PET‐based composites were compared with PET through TGA and tensile test, respectively. The LOI of the flame retardant composites increased from 21% of neat PET, up to 36% with the addition of 5% BP and 5% triphenyl phosphate to the matrix. Regarding the smoke density analysis, BP was determined as an effective smoke suppressant for PET. Enhanced tensile properties were obtained for the flame retardant PET‐based composites with respect to PET. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42016.  相似文献   
154.
Recently, the globalization of manufacturing industry systems has led to increase the competition in order to response to today’s demanding market especially in medium-size companies. The global competition requires the manufacturing systems to be flexible and reconfigurable specifically in the shop floor level where mechatronic devices reside. In this paper, a novel methodology for the development and structural modeling of industrial wireless sensors and actuators is presented in order to provide flexibility and reconfigurability to the mechatronic devices. The proposed methodology is based on the implementation of the IEC 61499 standard for the distributed control of mechatronic systems. The methodology also addresses the existing problems of this standard for capturing the system requirements in the development process. For this reason, the Unified Modeling Language is used in order to overcome this problem. A case study is presented in order to demonstrate the operational aspects of the proposed methodology.  相似文献   
155.
An analysis of the mechanics of large strain extrusion machining (LSEM), a constrained chip formation process, is presented for deformation processing of bulk alloys. The deformation field is shown to be narrowly confined and controllable, with attributes ranging from conventional deformation processing to severe plastic deformation. Controllable deformation parameters include strain/strain rate, hydrostatic pressure, temperature and deformation path. These attributes are highlighted in deformation processing of Mg AZ31B, an alloy of commercial significance but noted for its poor workability, into sheet and foil forms. Noteworthy features of the processing are suppression of segmentation, realization of a range of strains and deformation rates, engineering of microstructures ranging from conventional to ultrafine grained, and creation of sheet/foil from the bulk in a single step of deformation without pre-heating. Guidelines for realizing specific sheet attributes, and scalability of LSEM for production are analyzed and discussed.  相似文献   
156.
Carbon dioxide capture and separation requires robust solids that can stand harsh environments where a hot mixture of gases is often found. Herein, the first and comprehensive syntheses of porous sulfur‐bridged covalent organic polymers (COPs) and their application for carbon dioxide capture in warm conditions and a wide range of pressures (0–200 bar) are reported. These COPs can store up to 3294 mg g?1 of carbon dioxide at 318 K and 200 bar while being highly stable against heating up to 400 °C. The carbon dioxide capacity of the COPs is also not hindered upon boiling in water for at least one week. Physisorptive binding is prevalent with isosteric heat of adsorptions around 24 kJ mol?1. M06–2X and RIMP2 calculations yield the same relative trend of binding energies, where, interestingly, the dimer of triazine and benzene play a cooperative role for a stronger binding of CO2 (19.2 kJ mol?1) as compared to a separate binding with triazine (13.3 kJ mol?1) or benzene (11.8 kJ mol?1).  相似文献   
157.
We provide a detailed analysis of the use of minimal spanning graphs as an alignment method for registering multimodal images. This yields an efficient graph theoretic algorithm that, for the first time, jointly estimates both an alignment measure and a viable descent direction with respect to a parameterized class of spatial transformations. We also show how prior information about the interimage modality relationship from prealigned image pairs can be incorporated into the graph-based algorithm. A comparison of the graph theoretic alignment measure is provided with more traditional measures based on plug-in entropy estimators. This highlights previously unrecognized similarities between these two registration methods. Our analysis gives additional insight into the tradeoffs the graph-based algorithm is making and how these will manifest themselves in the registration algorithm's performance.  相似文献   
158.
A new, asymmetrical zinc phthalocyanine (aZnPc)‐functional photocurable copolymer was prepared by the combination of atom transfer radical polymerization and copper (I)‐catalyzed azide‐alkyne cyclo‐addition (CuAAC) click reaction and used as polymer matrix of polymer dispersed liquid crystal (PDLC) film. For this purpose, aZnPc was prepared through statistical condensation of 4‐tert‐butylphthalonitrile and 4‐pent‐4‐ynyloxyphthalonitrile. Double CuAAC click reaction between azido‐functional poly(methyl methacrylate‐co‐2‐(2‐bromoisobutyryloxy)‐ethyl methacrylate), terminal alkynyl‐substituted aZnPc, and 4‐ethynyl‐N,N‐dimethyl aniline yielded photocurable aZnPc‐functional copolymer. Thereby, synthesized copolymer was crosslinked in the presence of liquid crystalline mesogen 4′‐(octyloxy)‐4‐biphenylcarbonitrile by ultraviolet irradiation using benzophenone as initiator and ethylene glycol dimethacrylate as difunctional crosslinker. Thermal and optical properties of PDLC film were investigated by using differential scanning calorimetry and polarized optical microscopy. Smectic A liquid crystal mesophases were observed in both PDLC film and its mesogenic component 4′‐(octyloxy)‐4‐biphenylcarbonitrile. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41574.  相似文献   
159.
Coverage of artificial surfaces within seawater by fouling organisms is defined as biofouling. Although biofouling is a natural process, it has some disadvantages for shipping industry such as increased fuel consumption, and CO2 emission. Therefore, the ships' hull must be covered by antifouling (AF) or fouling release type coatings to overcome biofouling. In general, the so-called self-polishing AF paints contain biocides for preventing fouling organisms. Their concentrations and release rates from AF coatings are of great importance and they definitely affect both quality and cost of the coating. In the present study, we aimed at applying a new robust method. In this method, we used a model biocide, i.e., econea, to obtain its RP-HPLC optimization through artificial neural networks (ANN) and to see its antifouling performance. Column temperature, mobile phase ratio, flow rate, concentration and wavelength as input parameters and retention time as an output parameter were used in the ANN modeling. In conclusion, the R&D groups in AF paint industry may use RP-HPLC method supported with ANN modeling in further studies.  相似文献   
160.
本文以丙烯酰胺和丙烯酰氧基乙基三甲基氯化胺为原料 ,通过自由基聚合反应合成阳离子聚丙烯酰胺(CPAM)。利用红外光谱、13C核磁共振谱及凝胶渗透色谱对所合成的产物进行了表征。结果表明 ,本实验成功地合成了CPAM ,其平均分子量为 10 .4万。将所合成的CPAM用于废纸浆 ,研究其对纸张的增强作用。结果表明 ,该CPAM可明显改善纸页的物理性能 ,纸页的裂断长、撕裂指数及耐破指数明显提高  相似文献   
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