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71.
The current work expresses considerations about some of the differences of the fused flux CIS-F10 obtained by means of fragmentation in water and with an air jet. The comparisons are established taking into account their respective granulometric distributions, shapes and grain densities, as well as the energy and the time spent in the process of obtaining each of these variants. Criteria for the physical process of flux fragmentation with an air jet and its influence over the aspects formerly mentioned are also included. The principal findings were that the process for obtaining the fused flux CIS-F10 granulated with an air jet consumes 37% less energy and 25% less time than the one performed with pouring water. The solidness grade of the spherical grains, granulated with air, (with pycnometric density 2.31 g/cm3), with a granulometric distribution more continuous than that of the granules in water, contributes to the increase of the apparent density (11%) of the flux and promotes the creation of artificial granulometric distributions, counteracting the rolling effect during welding.  相似文献   
72.
介绍目前比较典型的塔式造粒生产复合肥的技术,指出造粒塔塔高选择的基本原则及高塔造粒生产复合肥工艺控制中的一些基本方法:原料选择与配方原则,熔融混合温度及混合时间的控制原则,造粒喷头的选择等。  相似文献   
73.
高塔造粒复合肥冷却新工艺   总被引:1,自引:0,他引:1  
赖涛 《磷肥与复肥》2009,24(5):64-65
提出以地下水为冷媒预冷却空气并对空气减湿的高塔造粒复合肥冷却新工艺。介绍其工艺流程、工艺设备以及实施效果,可使物料良好冷却,保持颗粒外观圆整度,降低生产成本。  相似文献   
74.
Abstract: The stability of microencapsulated fish oil prepared with 2 production processes, spray granulation (SG) and SG followed by film coating (SG-FC) using a fluid bed equipment, was investigated. In the 1st process, 3 types of fish oil used were based on the ratios of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (10/50, 33/22, and 18/12). Each type was emulsified with soluble soybean polysaccharide (SSPS) and maltodextrin to produce 25% oil powders. In the 2nd process, 15% film coating of hydroxypropyl betacyclodextrin (HPBCD) was applied to the granules from the 1st process. The powder stability against oxidation was examined by measurement of peroxide values (PV) and headspace propanal after storage at room temperature and at 3 to 4 °C for 6 wk. Uncoated powder containing the lowest concentration of PUFA (18/12) was found to be stable during storage at room temperature with maximum PV of 3.98 ± 0.001 meq/kg oil. The PV increased sharply for uncoated powder with higher concentration of omega-3 (in 33/22 and 10/50 fish oils) after 3 wk storage. The PVs were in agreement with the concentration of propanal, and these 2 parameters remained constant for most of the uncoated powders stored at low temperature. Unexpectedly, the outcomes showed that the coated powders had lower stability than uncoated powders as indicated by higher initial PVs; more hydroperoxides were detected as well as increasing propanal concentration. The investigation suggests that the film-coating by HPBCD ineffectively protected fish oil as the coating process might have induced further oxidation; however, SG is a good method for producing fish oil powder and to protect it from oxidation because of the “onion skin” structure of granules produced in this process.  相似文献   
75.
The purpose of this study was to evaluate the influences of intrinsic drug mechanical properties and different granulation binder delivery processes on the physical and mechanical properties of high drug load granulations after wet granulation. Formulations (80% w/w) of acetaminophen (APAP), metformin and aspirin, which are brittle, viscoelastic, and ductile, respectively; were granulated by high-shear wet granulation. Two modes of binder delivery for wet granulation, either conventional or binder foam, were investigated. Particle size, surface area and pore size of the granulations were characterized. Compacts were prepared at a solid fraction of 0.9 under tri-axial decompression and Hiestand indices (worst-case bonding index (BIw) and brittle fracture index (BFI)) of the compacts were determined. APAP formulations exhibited the smallest geometric mean particle sizes (dg) and showed only slight differences in dg values between the two granulation processes. Binder delivery mode affected mechanical properties of the granulated model drugs differently. Foam granulation appeared to enhance the granule plasticity for APAP while aspirin showed a mixed deformation mechanism based on both its high BIw and high BFI values. The higher BIw value for aspirin after foam granulation may be attributed to improved binder distribution among particles during granulation. On the other hand, conventional wet granulation improved the plasticity of metformin as measured by the higher BIw and lower BFI values. Therefore, conventional wet granulation process conferred advantages in manufacturability and product quality for metformin; as compared to foam granulation which did not enhance plasticity for metformin. Based on this study, a wet granulation process can be selected based on knowledge of the intrinsic drug mechanical properties.  相似文献   
76.
以重钙作磷源,用对辊冷压造粒工艺生产复混肥,可降低复混肥成本,增加产品中水溶性P2O5含量。重钙中的游离酸可用碳铵(用量为重钙的8%~10%)预中和,以改善物性。此外,介绍了高浓度(40%养分)和低浓度(25%养分)复混肥的配方。  相似文献   
77.
尿素熔融喷浆造粒生产复合肥有关问题的探讨   总被引:2,自引:2,他引:0  
在尿素熔融或尿液进行喷浆团粒法生产复合肥的过程中 ,存在 :尿素在熔融槽熔解慢 ;尿液管道易堵 ;成球较小、过度成球或出现扁平状颗粒 ;物料干燥后筛分困难 ;喷浆用齿轮泵磨损严重等问题。分析产生这些问题的原因及解决措施 ,改造后 ,造粒成球率由 5 0 %提高到 85 %~ 90 % ;含氮量精度控制± 1.5 % ;产品水分 <1.5 % ;产量提高 30 % ;蒸汽、动力、燃料消耗均下降 10 %~ 15 % ,产品质量提高。  相似文献   
78.
含金褐铁矿直接堆浸的初步探讨   总被引:1,自引:0,他引:1  
程裕钧 《黄金》1991,12(8):32-34
本文对吴家金矿含金褐铁矿石进行直接堆浸试验,取得较好指标(金浸出率达到75%)作了简要论述,并探讨了制粒堆浸失败的原因和多雨季节堆浸过程应注意的事项,为该地区泥质氧化矿石(铁帽型金矿)直接堆浸提供了成功的经验。  相似文献   
79.
大型挤压造粒机芯轴是非常重要的零件,为避免其失效破坏,本文分别采用有限元分析与传统理论力学计算对其强度进行验算。  相似文献   
80.
Electrically conducting adsorbent materials called Nyex™ 1000 & 2000 have already been reported with comparatively low adsorption capacity for various organic, biologically non-degradable and toxic compounds. Two composite adsorbents called CA1 & CA2 were synthesized using synthetic graphite-carbon black and expanded graphite-carbon black respectively. The aim of developing the new adsorbents was to increase the adsorption capacity along with good electrical properties. The developed adsorbents were characterized using N2 adsorption for specific surface area, Boehm surface titration for surface chemistry, bed electrical conductivity, laser size analyzer for average particle size, and scanning electron microscope (SEM) for particle morphology and shape. Then both the composite adsorbents were tested for the adsorption of acid violet 17 followed by an electrochemical regeneration. The adsorption study revealed that both the adsorbents had almost similar kinetic behavior with a significant increase in adsorption capacity for acid violet 17 (300 & 26 mg g−1 respectively) when compared with the adsorption capacity of previously developed electrically conducting materials called Nyex™ 1000 & 2000 (3.5 and 9 mg g−1 respectively). The composite adsorbent CA2 was successfully electrochemically regenerated by passing an electric charge of 138 C g−1 at a current density of 14 mA cm−2 for a treatment time of 60 min, whereas, the composite adsorbent CA1 could not be regenerated successfully. The regeneration efficiencies of CA2 were obtained at around 120% during five adsorption–regeneration cycles. The amount of actual charge passed of 138 C g−1 for achieving 100% regeneration efficiency was found to be similar with stoichiometrically calculated amount of charge. The amount of electrical energy required to oxidize each mg of adsorbed acid violet onto CA2 (24 J mg−1) was found to be significantly lower to that of Nyex™ 1000 & 2000 adsorbents (52 J mg−1 & 32 J mg−1 respectively).  相似文献   
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