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ABSTRACT:  The objective was to examine the effects of potassium lactate (KL) and raw-meat blend on the shelf-life of fresh-pork-sausage patties in lighted and unlighted display. Four fresh-pork-sausage blends (70% prerigor meat, 30% fresh-pork trim; 80%/20%; 90%/10%; and 100%/0%) were formulated ( n = 3) with 0% and 3% KL, and patties were displayed for 10 d at 4 °C in lighted display or for 7 d in unlighted display followed by 3 d in lighted display. Patties with KL had lower aerobic plate counts (APC), more stable color (greater a* and chroma, less visual discoloration), and less lipid oxidation ( P < 0.05) during display than did patties without KL. Patties in the light for 10 d were more discolored and had more lipid oxidation ( P < 0.05) than those in the dark for 7 d followed by the light for 3 d. Patties with KL in the light for 10 d had similar color ( P > 0.05) to patties without KL that were in the dark for the first 7 d. Adding KL resulted in similar color stability ( P > 0.05) among patties made from 80, 90, and 100% prerigor meat and greater color stability ( P < 0.05) than similarly formulated patties without KL. By using 3% KL, fresh-pork-sausage patty color stability was maximized, APC and lipid oxidation were minimized, and formulation costs can be decreased by using less-expensive fresh-pork trim for up to 20% of the blend. Adding KL also minimized the effects of display lighting on myoglobin and lipid oxidation.  相似文献   
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Two industrial gear oils, a reference paraffinic mineral oil with a special additive package for extra protection against micropitting and a biodegradable non-toxic ester, were characterized in terms of their physical properties, wear properties and chemical contents and compared in terms of their power dissipation in gear applications [Höhn BR, Michaelis K, Döbereiner R. Load carrying capacity properties of fast biodegradable gear lubricants. J STLE Lubr Eng 1999; Höhn BR, Michaelis K, Doleschel A. Frictional behavior of synthetic gear lubricants. Tribology research: from model experiment to industrial problem. Elsevier 2001; Martins R, Seabra J, Seyfert Ch, Luther R, Igartua A, Brito A. Power Loss in FZG gears lubricated with industrial gear oils: biodegradable ester vs. mineral oil. Proceedings of the 31th Leeds-Lyon symposium on tribology. Elsevier; to be published; Weck M, Hurasky-Schonwerth O, Bugiel Ch. Service behaviour of PVD-coated gearing lubricated with biodegradable synthetic ester oils. VDI-Berichte Nr.1665 2002.]. The viscosity–temperature behaviors are compared to describe the feasible operating temperature range.Standard tests with the Four-Ball machine and the FZG test rig [Winter H, Michaelis K. FZG gear test rig—desciption and possibilities. In: Coordinate European Council second international symposium on the performance evaluation of automotive fuels and lubricants; 1985.] characterize the wear protection properties. Biodegradability and toxicity tests are performed in order to assess the biodegradability and toxicity of the two lubricants.Power loss gear tests are performed on the FZG test rig using type C gears, for wide ranges of the applied torque and input speed, in order to compare the energetic performance of the two industrial gear oils. Lubricant samples are collected during and at the end of the gear tests [Hunt TM. Handbook of wear debris analysis and particle detection in liquids. UK: Elsevier Science; 1993.] and are analyzed by Direct Reading Ferrography (DR3) in order to evaluate and compare the wear particles concentration indexes of both lubricants.An energetic model of the FZG test gearbox is developed, integrating the mechanisms of power dissipation and heat evacuation, in order to determine its operating equilibrium temperature. An optimization routine allows the evaluation of the friction coefficient between the gear teeth for each lubricant tested, correlating experimental and model results.For each lubricant and for the operating conditions considered, a correction expression is presented in order to adjust the friction coefficient proposed by Höhn et al. [Höhn BR, Michaelis K, Vollmer T. Thermal rating of gear drives: balance between power loss and heat dissipation. AGMA Technical Paper; October 1996. pp 12. ISBN: 1-55589-675-8.] to the friction coefficient exhibited by these lubricants. The influence of each lubricant on the friction coefficient between the gear teeth is discussed taking into consideration the operating torque and speed and the stabilized operating temperature.  相似文献   
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In patients with rheumatoid arthritis the synovial membrane of the affected joint is infiltrated with lymphoid cells which may be arranged in structures resembling germinal centers. We have directly isolated such infiltrates to determine whether B-cell clones within them are selected and expanded in a process analogous to that which normally takes place in the germinal centers in secondary lymphoid organs. The data suggest that an antigen-driven process leads to the accumulation of B cells in the synovial membrane. The finding of identical sequences in consecutive sections suggests that under conditions of chronic stimulation, memory B cells may enter a stage of differentiation in which they proliferate without further accumulation of somatic mutations. Further we see intraclonal diversity which underlines the germinal center-like character of these infiltrates and demonstrates that a microenvironment is built up in this nonlymphoid tissue which supports antigen-dependent differentiation of B cells. This is the first demonstration, to our knowledge, of a germinal center-like reaction outside lymphoid tissue.  相似文献   
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In this article, we present a method to recover electrical parameters of filters embedded in a multiplexer for which scattering measurements are given. Unlike other approaches proposed for this problem, this method does not require a priori knowledge of the scattering parameters of the junction. This feature renders the procedure well suited for tuning purposes or for fault diagnosis. Technically, the algorithm starts with a rational approximation step, to derive a rational representation of certain scattering parameters of the multiplexer. This representation is then used in a second step to identify an electrical model of each filter. This second step relies on a rational interpolation technique used to extract the filter's responses. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:647–654, 2015.  相似文献   
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In this article, we present two methods to de‐embed the filters' responses from a diplexer whose junction is known. A weak identification problem is here described by means of a dual‐state junction and can be applied for general diagnosis of prototype diplexers. A strong identification problem based on rationality of the filters is also introduced here and is suited for a real‐time tuning process. This technique is based on a polynomial approximation derived analytically from the algebraic structure of the diplexer's response. Additional unknown delays violating the rational assumption can be moreover detected and estimated. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.  相似文献   
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ABSTRACT: Three experiments investigated cooking rate, endpoint temperature, post-cook holding time, and raw myoglobin redox-state effects on ground beef internal cooked color. In Experiment 1, patties were cooked to endpoint temperatures of 65.6°C, 71.1°C, 76.7°C, 82.2°C, or 87.8°C rapidly (1°C/s), slowly (0.2°C/s), or rapidly with 6-min post-cook holding time at 104°C. Patties cooked slowly to less than 76.7°C were more well done ( P < 0.05) in appearance than those cooked rapidly. Rapidly-cooked patties cooked to less than 82.2°C and held for 6 min after cooking had less pinkness, more myoglobin denaturation, and a more well-done appearance than did rapidly cooked patties with no holding time ( P < 0.05). In Experiment 2, increasing post-cook holding time (1, 3, 6, or 12 min) after rapid cooking to 71.1°C, 76.7°C, or 82.2°C decreased pinkness and increased myoglobin denaturation ( P < 0.05), with no benefit beyond 6 min ( P > 0.05). In Experiment 3, patties cooked rapidly to 71.1°C, 76.7°C, or 82.2°C from a predominantly raw oxymyoglobin state were less pink and had more denatured myoglobin than did those cooked from a predominantly deoxymyoglobin state ( P < 0.05). Prediction equations determined that 80% of myoglobin must be denatured to create a well-done appearance. Using a slow cooking rate, post-cook holding time, or cooking from a highly oxygenated state will increase myoglobin denaturation and foster a well-done appearance.  相似文献   
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We report the perinatal findings in a male fetus with congenital megacystis and anorectal malformations. A 17-year-old primipara was referred to our department at 13 weeks of gestation for management of a 4.6 x 3.8 cm massive intra-abdominal fetal mass consistent with megacystis. The fetal thorax was severely compressed. We used a 22-gauge needle to perform intrauterine fetal vesicocentesis, removing 30 ml of fetal urine, decreasing the fetal bladder diameter/crown-rump length ratio from 65.7 to 17%. Cytogenetic analysis revealed a 46, XY karyotype. Intermittent bladder aspiration was performed weekly from 13 to 20 weeks of gestation and every 2-3 weeks from 21 to 35 weeks of gestation for the purpose of decompression. Mild dilation of both renal pelves was noted beginning at 20 weeks of gestation, however, neither progression of hydronephrosis nor development of oligohydramnios was noted. At 36 weeks of gestation, a live male neonate was delivered with a normal phallus, duodenal atresia, mild congenital heart defects, a distended bladder, bilateral hydronephrosis, megaureters, imperforate anus with rectovesical fistula, cryptorchidism and bilateral vesicoureteric reflux. The postnatal renal function was normal. He underwent serial operations including colostomy, anoplasty with repair of rectovesical fistula, duodeno-duodenostomy, bilateral re-implantation of ureters, orchiopexy and reduction cystoplasty. At 20 months of age, the child had normal renal function. The intravenous pyelogram showed normal functional kidneys, moderate megaureters and moderate megacystis. He underwent clean intermittent catheterization for residual urine. The recurrent urinary tract infections were under control.  相似文献   
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High throughput coatings for photovoltaics – Contribution of sputtering technology to Paris Climate Goals Photovoltaics (PV) is one of the most important renewable energy sources whose expansion is needed to achieve the climate goals. The considerable drop down in the costs of PV based energy within the last 10 years has led to a very high degree of economic attractiveness for photovoltaics. This was made possible by new cell structures with higher efficiencies, lower material usage and utilization of scaling effects as well as automation in production. Highly efficient PVD coating processes, such as the magnetron sputtering, are increasingly being used in current crystalline PV cell types such as heterojunction or TOPCON solar cells. Thin film technologies are still the backbone for processing of the less material‐intensive thin‐film solar modules.  相似文献   
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