钨合金废料的资源再生利用技术

钨是一种稀有金属，钨合金具有高的强度、硬度，较好的耐高温性、耐密性和良好的电性能。广泛应用于航空航天工业、兵器工业、核工业、信息产业、汽车工业和钢铁工业等行业。目前，钨资源短缺，钨合金价格高、用量大，因此各国都把废弃的钨合金作为宝贵的第二钨资源加以再生利用。本文综述了钨合金的再生利用现状，分别总结了硬质合金、高比重合金、钨铜合金和钨材的再生利用技术，并利用生态环境材料的观点。对每种再生利用技术作了简单的评价。     

Cholesterol‐imprinted polymer receptor prepared by a hybrid imprinting method

A novel cholesterol‐imprinted polymer (CMIP‐H) was prepared by a hybrid method of covalent imprinting and non‐covalent imprinting. This approach involves the copolymerization of a template‐containing monomer, cholesteryl 2‐hydroxyethyl methacrylate carbonate, and a cross‐linker, followed by hydrolysis to afford a flexible guest‐binding site accompanied with the easy and efficient removal of a ‘sacrificial spacer’. The effect of solvent on the binding capacity of CMIP‐H towards cholesterol was studied, indicating that a good binding capacity towards cholesterol could be achieved in a less‐polar solvent. The binding experiments of CMIP‐H towards a series of structural analogues of cholesterol, including cholesterol acetate, progesterone and stigmasterol, were carried out in hexane. The results showed that CMIP‐H almost did not bind cholesterol acetate at all because the hydrogen‐bonding site is blocked. It exhibited a similar binding towards both cholesterol and stigmasterol, but much higher binding towards progesterone. Copyright © 2005 Society of Chemical Industry     

Study of a BGO calorimeter using electron and hadron beams from 1 to 50 GeV

A calorimeter of 25 bismuth germanate (BGO) crystals equipped with silicon photodiode readout has been tested at the CERN SPS in the energy range 1–50 GeV. The response for electrons has been shown to be linear in this energy range and the rms resolution obtained ( ) is approximately 1%, for E > 4 GeV. The electron/pion separation was found to be better than 1:500 in the energy range 1–20 GeV. Data on lateral and longitudinal shower development were compared with the results of a Monte Carlo simulation using the SLAC-EGS program and found to be in good agreement.     

Goppa geometric codes achieving the Gilbert-Varshamov bound

Based on s-zeta-functions of curves over finite fields, we show that Goppa geometry codes achieve the q-ary Gilbert-Varshamov bound for all prime powers q (including q=2)     

公路边坡培植柠条的探讨

介绍了河曲公路所处的自然环境 ,阐述了人工铲草的利与弊 ,进而提出了边坡培植柠条的效益分析 ,并对培植柠条的苗期管理及与养护生产的关系进行了介绍     

10kV配电室操作控制电源电压下降的解决措施

本提出了10kV配电室操作电压下降的现场解决方案。     

Grazing incidence reflection absorption Fourier transform infrared (GIRA-FTIR) spectroscopic studies on the ferroelectric behavior of poly(vinylidene fluoride–trifluoroethylene) ultrathin films

Grazing incidence reflection absorption Fourier transform infrared (GIRA-FTIR) spectroscopy was used to characterize the ferroelectric behavior of a thin poly(vinylidene fluoride–trifluoroethylene) P(VDF–TrFE) copolymer. The lab-built GIRA-FTIR apparatus allowed the heating and corona poling process to be carried out whilst collecting the GIRA spectra of the thin polymer film. The Curie transition from the ferroelectric to paraelectric phase was confirmed from the abrupt change in intensity of the 849 cm⁻¹ band in the RA-FTIR spectrum. It was found that the Curie temperature dropped dramatically when the film thickness was lowered to below a certain critical value of approximately 100 nm. The switching of the CF₂ dipoles in the ferroelectric crystals after applying the external electric field could be determined by monitoring the change in the 849 cm⁻¹ band intensity. For the 600 nm thick P(VDF–TrFE) film, the switching of the dipoles appears to occur almost instantaneously, while the kinetics of dipole switching of the 75 nm thick film were significantly retarded. The repeated switchability of the CF₂ dipoles upon the application of a bipolar cyclic electric field was also confirmed. The bistability of the film due to remnant polarization was also confirmed from the absorbance of the 849 cm⁻¹ band after removing the applied voltage during corona poling.     

Preparation of BaMgAl10O17∶Eu2+ and Its Phase Behavior in Microemulsion System

BaMgAl10O17∶Eu2 (BAM) was prepared in the microemulsion system and its phase behavior was studied. There exists a small region in the reverse microemulsion system where the dispersed particles are of spherical form. In this way, BAM blue phosphor with good dispersion can be synthesized. The microemulsion phase diagrams of the pseudo-ternary system (Triton X-100/cosurfactant-oil-BAM brine) were first established intuitively by the dilution method. The microstructure of microemulsions was determined through eyeballing, conductance technique, and polar optical microscopy. Its phase behavior is affected by various factors, such as temperature (room temperature, 30, 40 ℃), oil, surfactants, and cosurfactants in microemulsions. According to the phase diagrams, the microemulsion system of Triton X-100/1-hexanol-hexane-BAM brine was chosen to prepare the precursor. The BAM phosphor can be obtained via sintering the precursor at a comparatively low temperature. The phosphors were characterized by XRD and vacuum ultraviolet (VUV) spectra.     

提高开卷线纵剪机精度的研究

通过对纵剪机右立柱轴承间隙测量方法和左立柱导向结构的改进，保证了加工精度，易于操作，提高了生产效率。