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91.
Indium tin oxide (ITO) thin films were deposited by radio frequency (RF) magnetron sputtering onto glass substrates. The transparent and conducting ITO thin films were obtained on externally unheated glass substrate, without any post-heat treatment, and by varying the deposition process parameters such as the working pressure and the RF Power. The effect of the variation of the above deposition parameters on the structural, surface morphology, electrical, and optical properties of the thin films have been studied. A minimum resistivity of 2.36 × 10−4 Ω cm and 80% transmittance with a figure of merit 37.2 × 10−3 Ω−1 is achieved for the thin films grown on externally unheated substrate with 75 W RF power and 0.5 mTorr working pressure.  相似文献   
92.
Mucoepidermoid carcinoma (MEC) is often seen in salivary glands and can harbor MAML2 translocations (MAML2+). The translocation status has diagnostic utility as an objective confirmation of the MEC diagnosis, for example, when distinction from the more aggressive adenosquamous carcinoma (ASC) is not straightforward. To assess the diagnostic relevance of MAML2, we examined our 5-year experience in prospective testing of 8106 solid tumors using RNA-seq panel testing in combinations with a two-round Delphi-based scenario survey. The prevalence of MAML2+ across all tumors was 0.28% (n = 23/8106) and the majority of MAML2+ cases were found in head and neck tumors (78.3%), where the overall prevalence was 5.9% (n = 18/307). The sensitivity of MAML2 for MEC was 60% and most cases (80%) were submitted for diagnostic confirmation; in 24% of cases, the MAML2 results changed the working diagnosis. An independent survey of 15 experts showed relative importance indexes of 0.8 and 0.65 for “confirmatory MAML2 testing” in suspected MEC and ASC, respectively. Real-world evidence confirmed that the added value of MAML2 is a composite of an imperfect confirmation test for MEC and a highly specific exclusion tool for the diagnosis of ASC. Real-world evidence can help move a rare molecular-genetic biomarker from an emerging tool to the clinic.  相似文献   
93.
Solar still is a very simple device, which is used for solar distillation process. In this research work, double basin solar still is made from locally available materials. Double basin solar still is made in such a way that, outer basin is exposed to sun and lower side of inner basin is directly connected with evacuated tubes to increase distillate output and reducing heat losses of a solar still. The overall size of the lower basin is about 1006 × 325 × 380 mm, the outer basin is about 1006 × 536 × 100 mm Black granite gravel is used to increase distillate output by reducing quantity of brackish or saline water in the both basins. Several experiments have conducted to determine the performance of a solar still in climate conditions of Mehsana (latitude of 23°59′ and longitude of 72°38′), Gujarat, like a double basin solar still alone, double basin solar still with different size black granite gravel, double basin solar still with evacuated tubes and double basin solar still with evacuated tubes and different size black granite gravel. Experimental results show that, connecting evacuated tubes with the lower side of the inner basin increases daily distillate output of 56% and is increased by 60, 63 and 67% with average 10, 20 and 30 mm size black granite gravel. Economic analysis of present double basin solar still is 195 days.  相似文献   
94.
Crude oil fouling in a laboratory fouling unit was investigated. The study focused on the preheat-train heat exchangers located just before the crude unit furnace and operating at temperatures in excess of 200C. A fouling rate model developed using laboratory data from crude blends was used to predict the threshold conditions where negligible fouling was expected under refinery conditions. The results from the model were compared to actual data from a fouling unit located at a refinery. The article discusses factors that may explain the performance of the model and the observed discrepancies between fouling data obtained in the laboratory and the field.  相似文献   
95.
Solar energy is an abundant and secure source of vitality and thus is described as one of the most promising alternative energy options. Nevertheless, solar energy is intermittent in nature as there is no sun at night. Its total availability value is seasonal and is hooked on the meteorological conditions of locations. Hence, solar energy presents an unsteady energy resource. So, thermal energy storage will be necessary to save the available solar energy at a period of no load or when excessive solar energy is available, and to make up for the shortage of energy when the load is in need of energy. This article reviews the different energy storage materials tried by various researchers to improve the distillate output of solar stills.  相似文献   
96.
Maltulose precursors are produced due to chemical isomerization of the reducing end glucose units during enzyme liquefaction and autoclaving of starch in the enzyme-enzyme process of glucose manufacture. The precursors are hydrolyzed during subsequent saccharification with amyloglucosidase to form maltulose as one of the products. Temperature, pH and DE of the liquefied starch during autoclaving and α-amylase treatment are important factors in controlling precursor formation, low temperature, low pH and low DE resulting in less maltulose formation. Acid liquefaction prior to saccharification does not result in maltulose precursor formation. Blocking of the reducing end glucose unit by hydrogenation to sorbitol prevents the formation of maltulose; maltitol is produced instead.  相似文献   
97.
98.
Biological processes have been employed in industry for centuries. However, recent advances in both cell and molecular biology have permitted more confident predictions that a given product can be produced by a biological process or organism at a reasonable cost. Genetic manipulation has become a practical and quite general proposition. This advance has evolved into a separate discipline known as biotechnology which has economic potential as important as atomic physics, electronics, and microelectronics. These developments in biotechnology are as applicable to brewer's yeast strains as they are to any other biological system. With the advent of spheroplast fusion and transformation, the capability exists to ‘modify’ existing yeast strains to enable them to ferment at a faster rate, tolerate high concentrations of ethanol, alter their flocculation properties, increase the number of metabolisable sugars, adjust the metabolic byproducts, etc. Fusion has been found to be too non-specific to genetically modify existing brewer's yeast strains in a controllable fashion; nevertheless, it is an invaluable technique for producing novel strains from brewing and other industrial strains. Transformation, particularly with the aid of recombinant DNA techniques, is a more subtle method for introducing single gene traits into strains. However, before such manipulations can be realistically undertaken, detailed biochemical knowledge of the system to be incorporated or modified must be available.  相似文献   
99.
Relational query languages can effectively express continuous queries on data streams after modest extensions. However, implementing such queries efficiently in data stream management systems requires major changes in execution models and optimization techniques. In particular, finer-granularity execution models that are conducive to effective time-stamp management and response-time optimization must replace databases' relational algebra schemes. This article introduces such a model and uses it to solve the idle-waiting problems of data stream operators, such as unions, joins, and aggregates over windows with slides.  相似文献   
100.
Underwater wireless sensor network (UWSN) is a network made up of underwater sensor nodes, anchor nodes, surface sink nodes or surface stations, and the offshore sink node. Energy consumption, limited bandwidth, propagation delay, high bit error rate, stability, scalability, and network lifetime are the key challenges related to underwater wireless sensor networks. Clustering is used to mitigate these issues. In this work, fuzzy-based unequal clustering protocol (FBUCP) is proposed that does cluster head selection using fuzzy logic as it can deal with the uncertainties of the harsh atmosphere in the water. Cluster heads are selected using linguistic input variables like distance to the surface sink node, residual energy, and node density and linguistic output variables like cluster head advertisement radius and rank of underwater sensor nodes. Unequal clustering is used to have an unequal size of the cluster which deals with the problem of excess energy usage of the underwater sensor nodes near the surface sink node, called the hot spot problem. Data gathered by the cluster heads are transmitted to the surface sink node using neighboring cluster heads in the direction of the surface sink node. Dijkstra's shortest path algorithm is used for multi-hop and inter-cluster routing. The FBUCP is compared with the LEACH-UWSN, CDBR, and FBCA protocols for underwater wireless sensor networks. A comparative analysis shows that in first node dies, the FBUCP is up to 80% better, has 64.86% more network lifetime, has 91% more number of packets transmitted to the surface sink node, and is up to 58.81% more energy efficient than LEACH-UWSN, CDBR, and FBCA.  相似文献   
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