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Copper-clad aluminum wires are extensively applied in aerospace, telecommunications, national defense industry, and other fields, because of the combined advantages of the excellent conductivity, thermal conductivity, and low contact resistance of copper and the low density, corrosion resistance, and low costs of aluminum. In this study, a composite wire with high interfacial bonding quality was obtained by hot rotary swaging, which can be utilized in manufacturing to achieve high efficiency and high quality because of its feature of the large single-pass deformation. The processed wire was then prepared by drawing into micro-wires, and given this, a simple, inexpensive, and highly efficient method for preparing micro-wires was developed in this study. Copper-clad aluminum wires with a diameter of φ65 μm, uniformly thick coating, glossy surface, and good interfacial bonding were prepared by the hot rotary swaging-drawing method. The rotary swaging parameters and the microstructure and interfacial bonding of the composite wire were studied, and the effects of drawing and intermediate annealing on its microstructure and properties were discussed. The results show that the reasonable swaging parameters are 350℃ swaging temperature with 40% single-pass deformation. After the rotary swaging, dynamic recrystallization microstructures and interface diffusion layer with thickness of 0.7 μm are formed. The optimum annealing parameter is 350℃/30 min (350℃ annealing temperature with 30 min annealing time), under which the elongation reaches 35.7%, the thickness of interface diffusion layer is 2.1 μm, and the copper layer and the aluminum core are recrystallized with the formation of equiaxed grains. When the annealing temperature exceeds 350℃, copper and aluminum grains and the interface layer thickness increase, which will lead to a lower wire elongation. A wire of φ0.96 mm is fabricated by a 15%-20% single-pass deformation, and then the φ65 μm diameter wire is manufactured by an 8%-15% single-pass deformation without annealing. In the drawing process, 〈111〉 silk texture appears in the copper layer and the aluminum core.

With the development of social networks, more and more studies utilize social information to improve the performance of traditional recommendation algorithms. However, most of the existing recommendation algorithms ignore the diversity of user interests and do not consider the aspects that users care about in different social dimensions, resulting in poor recommendation quality. In order to solve this problem, a recommendation method that considers both global latent factors and the specific latent factors of different subsets is proposed. The recommendation process considers both the user's shared preferences and the user's specific preferences in different subsets. This method first divides users into different subsets according to their social relationships, based on the intuition that users participate in different social dimensions, and are interested in different items. Secondly, the truncated singular value decomposition technique is used to model the user s rating of items, among which the global factors capture levels shared by users, while specific latent factors of different user subsets capture specific levels of user concern. Finally, global and local latent factors are combined to predict user ratings for unscored i-tems. Experiments prove that the method is feasible and effective. [ABSTRACT FROM AUTHOR]

Didymodon mesopapillosus J. Kou, X.-M. Shao & C. Feng is described and illustrated as a new species from Tibet, China. It is characterized mainly by its ovate to ovate-lanceolate leaves appressed to weakly erect when dry, margins recurved from leaf base to apex, laminal cell superficial walls markedly thicker than the internal walls, laminal papillae present only on both sides of costa, short-excurrent costa, undifferentiated basal cells and differentiated perichaetial leaves. This species is compared with similar species and its ecology is discussed. [ABSTRACT FROM AUTHOR]

The key of vacuum preloading method to ground stabilization technique is formed under the diaphragm seal, and maintained vacuum degree, the equipment is significant. The vacuum extraction equipment for traditional vacuum preloading usually uses jet pump. In this part of the project area, it used the new type vacuum equipment, which has saved the electricity and building materials, and remarkable economic and environmental benefits under the precondition of construction quality, and it is suitable for wildly used in large fields. [ABSTRACT FROM AUTHOR]

In our study, 198 types of pesticides in 120 types 333 lots of traditional Chinese medicine (TCM), which were reasonably classified according to its matrix property, were determined by using the pretreatment platform and gas chromatography-mass spectrometry method. As a result, 158 were contaminated with pesticides. However, the content of pesticides in most TCM was very low. In addition, types of pesticides were different in different part of materia medica. In conclusion, the current status of pesticide residues pollutants in TCM was summarized, and the result can provide proof for the formulation of maximum residue limit. The new species of herbs and the new detecting index should be electively monitored in Chinese Pharmacopeia.

Objective: To investigate the feasibility and techniques for purifying epigallocatechin-3-gallate (EGCG) by high speed countercurrent chromatography (HSCCC)., Methods: A HSCCC unit was used for the purification of EGCG from the extracts of tea., Results: The preferable solvent system was composed of Ether-Ethyl Acetate-H2O (4:10: 25, V/V), and the preferable technical conditions were as follows: the temperature was 35 degrees C, the rotation speed was 800 r/min and the mobile phase flow-rate was 2.5 mL/min., Conclusion: The purity of the obtained EGCG sample determined by high performance liquid chromatography (HPLC) is 95%.

Objective: To investigate the feasibility and technology for purifying Ganodermna lucidum polysaccharide (GLP) by ultrafiltration., Methods: A spire roll ultrafiltration unit was selected to purify GLP., Results: Purity of 73.5% and recovery ratio of 69.4% for GLP were obtained by using a membrane with cut-off molecular mass of 6000, while operating temperature, pressure and time were 45-50 degrees C, 0.6 MPa and 45 min, respectively., Conclusion: Ultrafiltration is one of the new feasible methods for the purification of GLP.

Objective: To isolate and purify Chlorogenic acid from Eucommia ulmoides leaves by ultrafiltration technique., Methods: Chlorogenic acid transferring ratio was investigated by temperature, pressure, time, cut-off molecular mass., Results: The optimal conditions for the ultrafiltration technique were finally determined. It was found that, for the membrane with a cut-off molecular mass of 20000, when the temperature, pressure, time were respectively 40 degrees C, 0.36 MPa, 20 minutes and adding 24L water, yield of Chlorogenic acid was 99.38%., Conclusion: High Chlorogenic acid transfering ratio can be gotten by ultrafiltration technique, which is helpful to the further isolation and purification of Chlorogenic acid in the subsequent process.