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81.
82.
农药悬浮剂的开发现状和展望 总被引:4,自引:0,他引:4
悬浮剂比可湿性粉剂有更多优点,如无粉尘、悬浮率高、润湿性好、较低的包装体积和生物效率高。论述了农药悬浮剂的进展、基本组成、前景和加工技术,较详细地讨论了悬浮剂剂型的物理稳定性和分散剂的选择以及影响悬浮剂物理稳定性的主要技术障碍——分子长大现象,并从原理、结构设计、制剂技术等多方面总结了多层静电屏蔽系统这一新制剂技术的研究情况。 相似文献
83.
V. Venugopal F. Shahidi Dr. Tung‐Ching Lee 《Critical reviews in food science and nutrition》1995,35(5):431-453
Fish is a rich source of easily digestible protein that also provides polyunsaturated fatty acids, vitamins, and minerals for human nutrition. Nonetheless, a large proportion of total landed fish remains unused due to inherent problems related to unattractive color, flavor, texture, small size, and high fat content. Most of these underutilized fish belong to the abundantly available pelagic species, which are landed as bycatch, and some are unconventional species such as krill. Although some species are used industrially for fish meal manufacture, a need for their conservation and utilization for human consumption has been recognized in order to prevent post‐harvest fishery losses. Recovery of flesh by mechanical deboning and development of value‐added products are probably the most promising approaches. This article discusses various possibilities for product development using mince from low‐cost fishery resources. These include surimi and surimi‐based products, sausages, fermented products, protein concentrates and hydrolysates, extruded products, and biotechnological possibilities. The dual advantages of this approach, namely, finding ways for better utilization of low‐value fish species and providing protein‐rich convenience foods, have been pointed out. However, the key to the success of this approach depends largely on the market strategies utilized. 相似文献
84.
Role of serum viscosity and of pulp content in the vacuum belt drying of pure fruit juices 总被引:1,自引:0,他引:1
ENRICO MALTINI RENATO NANI GIANNI BERTOLO 《International Journal of Food Science & Technology》1992,27(5):531-539
Vacuum Belt Drying of fruit juice concentrates may be a satisfactory alternative to freeze drying where cost is a limiting factor, and to spray drying where the addition of large amounts of 'carriers', e.g. maltodextrin or glucose syrups, are required to avoid collapse and sticking of the product.
The rheological and structural properties and the drying behaviour of some juice concentrates have been studied in relation to the collapse phenomenon, which is a structure transition associated with the mechanical properties of the system.
Collapse during drying has proved to be mainly related to the viscosity (consistency) of the soluble fraction of the concentrate, i.e. the 'serum', while there is no evidence of an effect of the suspended phase (pulp).
By properly adjusting the serum consistency of the juice with selected pectolytic enzymes and by appropriate mixing of the mash derivatives, apple, pear, apricot, and peach concentrates have been successfully dehydrated by vacuum belt drying, without any addition of 'carrier'-supporting materials. The consistency index of the concentrate serum may be used to assess the suitability of the juice for drying. 相似文献
The rheological and structural properties and the drying behaviour of some juice concentrates have been studied in relation to the collapse phenomenon, which is a structure transition associated with the mechanical properties of the system.
Collapse during drying has proved to be mainly related to the viscosity (consistency) of the soluble fraction of the concentrate, i.e. the 'serum', while there is no evidence of an effect of the suspended phase (pulp).
By properly adjusting the serum consistency of the juice with selected pectolytic enzymes and by appropriate mixing of the mash derivatives, apple, pear, apricot, and peach concentrates have been successfully dehydrated by vacuum belt drying, without any addition of 'carrier'-supporting materials. The consistency index of the concentrate serum may be used to assess the suitability of the juice for drying. 相似文献
85.
某低品位铅锌硫化矿浮选试验研究 总被引:1,自引:1,他引:0
袁来敏 《有色金属(选矿部分)》2014,(3):14-17,66
某硫化铅锌矿含铅锌原矿品位低、嵌布粒度细、伴生关系复杂。通过多种方案的比较,采用优先浮选抑锌浮铅的选别流程,试验采用乙硫氮作为优先选铅的捕收剂,石灰作为调整剂以及黄铁矿的抑制剂,硫酸锌和亚硫酸钠作为闪锌矿的抑制剂,之后利用硫酸铜作为闪锌矿的活化剂,用丁基黄药作为捕收剂来实现铅与锌的有效分离。试验获得铅精矿含铅51.00%、铅回收率86.63%、含银518 g/t、银回收率47.41%,锌精矿含锌51.20%、锌回收率85.27%、含银234 g/t、银回收率38.38%。 相似文献
86.
In the cheese industry, the concentration of milk using ultrafiltration for continuous soft and fresh cheese production is standard technology. The object of the work presented here was to produce a semi-hard cheese of quality and composition comparable to that of traditionally made cheese from highly concentrated microfiltered milk retentate. Two different membrane systems were tested for the production of high viscous milk retentate with high dry matter content. For milk containing 3.2% fat and skim milk, a concentration factor of 6.6 and 9.1 respectively was obtained using the MF/UF/UF pilot plant fitted with cassette modules. Milk containing 3.2% fat was concentrated in batches by a factor of 5.7 in the pilot plant using a ceramic membrane. Using minimal curd separation, a semi-hard one day old cheese with a dry matter of 533 g/kg, moisture on a fat-free basis (MFFB) of 626 g/kg and fat on a dry basis (FDB) value of 478 g/kg was made from the milk retentate produced with the ceramic module. The ripened cheese fulfilled the legal requirements of a traditionally produced semi-hard cheese with superb sensory qualities. Using the MF/UF/UF plant, a dry matter of 495 g/kg (MFFB 669 g/kg, FDB 493 g/kg) was achieved in a semi-hard cheese made from skim milk retentate. Our results suggest that by using a larger spacer distance in the last loop of the MF/UF/UF plant, combined with new hybrid technologies, semi-hard cheese production from full concentrate milk will soon become possible. 相似文献
87.
微波加热含碳铁矿粉还原矿相结构研究 总被引:11,自引:1,他引:10
微波加热含碳铁矿粉还原矿相结构分为金属铁、浮氏体和渣相结构。矿粉颗粒围绕煤粉颗粒进行还原,形成星点状金属铁,进而形成环带状结构。由于矿-煤颗粒界面间还原出的金属铁厚度增大,使初始直接还原反应减弱,尚未还原的FeO核心依靠碳气化生成的CO和金属铁中碳的扩散继续还原,形成蠕虫状金属铁连晶结构。浮氏体对微波具有一定的吸收性,在微波场中自身热碎裂,可加速碳热还原。渣相含有变价铁元素,对微波有一定的吸收能力,有利于渣相中复杂铁氧化物的还原。 相似文献
88.
A modified procedure for extraction of total lipids from whey protein concentrates was developed such that stable emulsion
with extracting solvents was avoided and the solvent system remained monophasic. Nonlipid contaminants from the extract were
removed using gel filtration instead of traditional aqueous washing to prevent any loss of polar lipids. The extraction of
total lipids by the modified procedure was complete and comparable with a reference procedure. Traditional thin-layer chromatography
is tedious and more qualitative than quantitative for lipid class separation. Total lipids were further separated into free
fatty acids, phospholipids, cholesterol ester, triacylglycerol, cholesterol, diacylglycerol, and monoacylglycerol, using modified
solid phase extraction procedure. Columns with 2 g amino propyl packing allowed separation of up to 80 mg of total lipids
into lipid classes gravimetrically. The values for anhydrous milk fat for all lipid classes agreed with those in the literature.
Separation of total lipids into lipid classes with solid phase extraction is easy, quantitative, and can also be performed
on a preparative scale. 相似文献
89.
对金昌冶炼厂Ausmelt炉烟气单体硫超标的原因进行了分析,介绍了采取的措施及取得的效果。 相似文献
90.