钛白粉副产物硫酸亚铁生产硫酸铵和氧化铁红的研究

以硫酸法钛白粉副产物绿矾为原料 ,生产硫酸铵和铁红粉 .用含臭氧 ( 5 0 0mg/h)的空气在5 0℃将FeCO3氧化成Fe2 O3·nH2 O .通过煅烧制铁红产品 ,其质量达HO0 1 - 0 2 一级品要求 ;硫酸铵通过净化、除杂、浓缩、结晶 ,生产一级品硫铵 .实验证明 ,本工艺氧化时间短 ,产品质量稳定     

Occlusion-resistant camera design for acquiring active environments.

In this article, we present a detailed theoretical analysis and a prototype implementation of a family of cameras designed with the explicit goal of detecting and removing interfering dynamic occluders in real time, during live capture, as opposed to fixing the resulting artifacts a posteriori. Such an early-acquisition approach improves efficiency: more valid samples are acquired faster without worrying about moving occluders. One option for designing a camera to be unaffected by moving occluders is to sample through the occluder, but true x-ray-like vision is technically impractical. Another option is to sample around the occluder using a camera with a large effective aperture, but such an approach requires a bulky acquisition device. Yet another possibility of sampling around an occluder is to rely on second and higher order reflected rays that indirectly sample surfaces not directly visible. However, devising an acquisition device sufficiently sensitive and efficient to capture large environments using reflected rays will remain challenging for the foreseeable future.     

Observation of atomic steps on CaCO3 crystal surface

By using scanning polarization force microscopy,the deliquescence process and the atomic steps on the cleavage surface of CaCO3 in air were studied in situ.Under an exposure to medium umidity(-57%),the sloiw step movement has been observed.     

钒冶炼焙烧添加剂选择研究

对小型钒冶炼厂焙烧工艺所用添加剂进行改进的可能性进行了探讨，研究了几种常用添加剂的焙烧条件，分析比较了其性能，提出用ＮａＣｌ－Ｎａ２ＣＯ３作焙烧添加剂替代ＮａＣｌ可大幅度减少大气污染，提高冶钒转化率；且不改变工艺流程，无需设备投资，具有较好的经济效益和环境效益。     

Parathion degradation and toxicity reduction in solar photocatalysis and photolysis.

The solar photocatalytic degradation of methyl parathion was investigated using a circulating TiO2/solar light reactor. Under solar photocatalysis condition, parathion was more effectively degraded than solar photolysis and TiO2-only conditions. With solar photocatalysis, 20 mg/L of parathion was completely degraded within 60 min with a TOC decrease of 63% after 150 min. The main ionic byproducts during photocatalysis recovered from parathion degradation were mainly as NO3-, NO2- and NH4+, 80% of the sulphur as SO4(2-), and 5% of phosphorus as PO4(3-). The organic intermediates 4-nitrophenol and methyl paraoxon were also identified, and these were further degraded in solar photocatalytic condition. Two different bioassays (Vibrio fischeri and Daphnia magna) were used to test the acute toxicity of solutions treated by solar photocatalysis and photolysis. The Microtox test using V. fischeri showed that the toxicity expressed as EC50 (%) value increased from 5.5% to >82% in solar photocatalysis, indicating that the treated solution is non-toxic, but only increased from 4.9 to 20.5% after 150 min in solar photolysis. The acute toxicity test using D. magna showed that EC50 (%) increased from 0.05 to 1.08% under solar photocatalysis, but only increased to 0.12% after 150 min with solar photolysis, indicating the solution is still toxic. The pattern of toxicity reduction parallels the decrease in TOC and the parathion concentrations.     

Highly Cooperative Tetrametallic Ruthenium-mu-Oxo-mu-Hydroxo Catalyst for the Alcohol Oxidation Reaction

The tetrametallic ruthenium-oxo-hydroxo-hydride complex {[(PCy(3))(CO)RuH](4)(mu(4)-O)(mu(3)-OH)(mu(2)-OH)} (1) was synthesized in two steps from the monomeric complex (PCy(3))(CO)RuHCl (2). The tetrameric complex 1 was found to be a highly effective catalyst for the transfer dehydrogenation of alcohols. Complex 1 showed a different catalytic activity pattern towards primary and secondary benzyl alcohols, as indicated by the Hammett correlation for the oxidation reaction of p-X-C(6)H(4)CH(2)OH (rho = -0.45) and p-X-C(6)H(4)CH(OH)CH(3) (rho = +0.22) (X = OMe, CH(3), H, Cl, CF(3)). Both a sigmoidal curve from the plot of initial rate vs [PhCH(OH)CH(3)] (K(0.5) = 0.34 M; Hill coefficient, n = 4.2+/-0.1) and the phosphine inhibition kinetics revealed the highly cooperative nature of the complex for the oxidation of secondary alcohols.     

Synthesis and characterization of poly(N‐vinyl‐2‐pyrrolidone) grafted sodium alginate hydrogel beads for the controlled release of indomethacin

Graft copolymers of sodium alginate (NaAlg) with N‐vinyl‐2‐pyrrolidone were prepared using azobisisobutyronitrile as initiator. The graft copolymers (NaAlg‐g‐PVP) were characterized with Fourier transform infrared spectroscopy, elemental analysis, and differential scanning calorimetry. Polymeric hydrogel beads of NaAlg and NaAlg‐g‐PVP were prepared by crosslinking method using glutaraldehyde (GA) as a crosslinker in the hydrochloric acid catalyst (HCl) and these beads were used to deliver anti‐inflammatory drug, indomethacin (IM). Chemical stability of the IM after encapsulation into beads was confirmed by FTIR. Preparation conditions of the NaAlg‐g‐PVP beads were optimized by considering the percentage entrapment efficiency, particle size, swelling capacity and their release data. In vitro release studies were performed in simulated gastric fluid (pH 1.2) for the initial 2 h, followed by simulated intestinal fluid (pH 7.4) for 4 h. Effects of GA concentration, exposure time to GA, drug/polymer (d/p) ratio, and concentration of HCl on the release of IM were discussed. It was observed that IM release from the beads decreased with increasing GA concentration and exposure time. IM release also decreases with increasing d/p ratio and HCl concentration. The highest IM release was obtained to be 77% for beads crosslinked with 0.027M GA. Swelling experiments were also performed to compute molecular mass between crosslinks of the beads. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Synthesis and characterization of a novel proton‐exchange membrane for fuel cells operating at high temperatures and low humidities

The synthesis of a p‐toluidine/formaldehyde (PTF) resin was performed, and the effects of the molar ratio of the individual monomers and the polymerization conditions on the structure of the PTF resin were studied. Fourier transform infrared and ¹³C‐NMR spectra were used to characterize the PTF. Wide‐angle X‐ray diffraction patterns revealed the crystalline structures of various PTFs. Polarized optical microscopy revealed that the molar ratio of the monomers had a strong effect on the crystalline morphologies. A longer polymerization time turned out a polymer with a higher intrinsic viscosity and molecular weight, which led to differences in the proton conductivity. All of the PTFs showed a higher proton conductivity than a commercial Nafion membrane at 90–100°C and 0% relative humidity. The proton conductivity of the PTF series could be improved by sulfonation with sulfuric acid and could be maintained after blending with polyurethane. Pure methanol could be used as a fuel source because of the insolubility and nonwetting properties of PTF in methanol to increase the output current density for a PTF membrane electrode assembly. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Shear-induced crystallization of poly(phenylene sulfide)

The crystalline morphology of poly(phenylene sulfide) (PPS) isothermally crystallized from the melt under shear has been observed by polarized optical microscope (POM) equipped with a CSS450 hot-stage. The shish–kebab-like fibrillar crystal structure is formed at a higher shear rate or for a longer shear time, which is ascribed to the tight aggregation of numerous oriented nuclei in the direction of shear. The crystallization induction time of PPS decreases with the shear time, indicating that the shear accelerates the formation of stable crystal nuclei. Under shear, the increase of spherulite growth rate results from highly oriented chains. The melting behavior of shear-induced crystallized PPS performed by differential scanning calorimetry (DSC) shows multiple melting peaks. The lower melting peak corresponds to melting of imperfect crystal, and the degree of crystal perfection decreases as the shear rate increases. The higher melting peak is related to the orientation of molecular chains. These oriented molecular chains form the orientation nuclei which have higher thermal stability than the kebab-like lamellae that are developed later. A new model based on the above observation has been proposed to explain the mechanism of shish–kebab-like fibrillar crystal formation under shear flow.