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Nitrogen-doped (N-doped) carbon, denoted as Fe–UF–CNx, is synthesized through nitridation of an iron-doped gel precursor on the Vulcan support. It exhibits a legitimate activity on catalyzing oxygen reduction reaction (ORR). Its polarization curve, measured with a rotating disk electrode in O2-saturated H2SO4, indicates Fe–UF–CNx has a widely distributed ORR activity and a high onset potential 0.859 V. The widely distributed activity originates from its complex nitrogen sites on the graphitic sheet, evidenced by the broad N1s spectrum of Fe–UF–CNx, which is featured with twin peaks of nearly equal intensity for pyridinic and pyrrolic nitrogens. The high onset potential suggests, despite an overall mediocre activity, the Fe–UF–CNx activity involves a small fraction of very active sites. When properly joining with the RuSe2 pyrite nanoparticles, the high potential active sites of Fe–UF–CNx uplift the ORR activity to the level of carbon-supported Pt catalyst. The platinum–level activity is manifested by a small half-wave potential difference 0.03–0.04 V between the joint catalyst of RuSe2–Fe–UF–CNx and the commercially available Pt/C catalyst. Additional merits of RuSe2–Fe–UF–CNx, such as high stability, methanol tolerance, low peroxide yield, are also measured and discussed.

The compressive strength and piezoresistive property of cement mortar with low adding level of multi-walled carbon nanotubes (MWCNTs) were investigated. Experimental results showed that the compressive strength of the MWCNTs/cement mortars increased with the adding amount of MWCNTs content for all the curing ages. Silica fume promoted the compressive strength development by well bonding with MWCNTs and filling effect. The electrical resistance changed synchronously with the compressive strength and the amount of the changes varied with the stress and MWCNTs addition levels. Higher MWCNTs doping level improved the piezoresistive sensitivity of the mortar. The mortar with silica fume (5-10% by weight of cement) exhibited better piezoresistive response than that without silica fume at the same MWCNTs doping levels.

The slag based geopolymers materials are synthesized at ambient temperature by using fly ash (FA) and ground granulated blast furnace slag (GGBFS) as the main starting materials, and NaOH and soluble glass together as activators. The influence of the mix proportion between GGBFS and FA on the strength and reaction products was investigated. The products obtained were characterized by means of XRD, FTIR spectroscopy and FE-SEM coupled with EDX. The results show that a great increase in compressive strength appears when the replacement percentage of GGBFS exceeds 30wt. %, the resultant products are mainly amorphous materials (amorphous aluminosilicate and/or C-S-H gel) and much more compact, homogeneous, and uniform when the amorphous aluminosilicate is increasingly turned into C-S-H gel with the increasing replacement percentage of GGBFS.

Four novel derivatives of 1,1′-bi-2-naphthol have been prepared and the structures of these compounds characterised by IR, MS, 1H and 13C NMR spectroscopy and elemental analysis. The enantioselective recognition of these sensors has been studied by fluorescence titration and 1H NMR spectroscopy. The sensors exhibited different chiral recognition abilities towards N-Boc-protected amino acid anions and formed 1:1 complexes between the host and the guest. Sensors exhibit excellent enantioselective fluorescent recognition ability towards the amino acid derivatives.

A new strategy involving the introduction of the common cationic surfactant cetyltrimethyl ammonium bromide (CTAB) for the cathodic electrodeposition of ZnO electrodes from Zn(NO3) solutions by cyclic voltammetry has been developed. Frizzily lamellar and porous ZnO films were obtained. The deposited films were characterized by X-ray diffraction (XRD) in the range of low-angle and wide-angle, X-ray photoelectron Spectroscopy (XPS), scanning electron microscopy (SEM), and UV-Vis transmittance spectroscopy. The role of the CTAB was also discussed. Under the optimal contents of CTAB, the XRD pattern shows that the as-synthesized ZnO is lamellar nanostructure and SEM image demonstrates that porous and frizzyly lamellar ZnO crystals are formed; XPS spectra of as-deposited film shows that the electrodeposition mainly consists of Zn and O and the Optical transmittance spectra of ZnO film indicates that optical transmittance is low and gradually decreases with the wavelength lessening in the visible light region. Mechanisms are proposed for the electrochemical deposition and the beneficial role of CTAB.

The complex [Mn(PMBP)2(CH3OH)2] of manganese(II) with 1-phenyl-3-methyl- 4-benzoyl-5-pyrazolone (PMBP) was prepared and characterized by elemental analysis, thermal analysis, IR. The crystal structure of the complex determined by single crystal X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and Mn(II) atom is six-coordinated and is in a meridional octahedral environment. The compound crystallizes in the monoclinic system, space group P 2(1)/c, with a = 11.038(10) A, b = 16.254(15) A, c = 9.540(9) A, α = 90.00°, β = 105.112(10)°, γ = 90.00°, V = 1,652(3) A3, D x = 1.354 g cm−3 and Z = 2. The thermal decomposition kinetics of the complex was investigated under nonisothermal conditions using the Achar differential method and the Coats–Redfern integral method. The complex [Mn(PMBP)2(CH3OH)2] of manganese(II) with 1-phenyl-3-methyl- 4-benzoyl-5-pyrazolone (PMBP) was prepared and characterized by elemental analysis, thermal analysis, IR. The crystal structure of the complex determined by single crystal X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and Mn(II) atom is six-coordinated and is in a meridional octahedral environment. The compound crystallizes in the monoclinic system, space group P 2(1)/c, with a = 11.038(10) A, b = 16.254(15) A, c = 9.540(9) A, α = 90.00°, β = 105.112(10)°, γ = 90.00°, V = 1,652(3) A3, D x = 1.354 g cm−3 and Z = 2. The thermal decomposition kinetics of the complex was investigated under nonisothermal conditions using the Achar differential method and the Coats–Redfern integral method.

The setting times and strength of cement substituting kiln dust-activated coal gangue for part of clinker was tested. The performance of sulphate resistance and restraining alkali silica reaction (ASR) of cement with 30% kiln dust-activated coal gangue was studied. The results indicate: the setting times of cement mixed with kiln dust-activated coal gangue is delayed and the early strength and later strength of cement with 10% kiln dust-activated coal gangue is improved to some extent, but the strength is reduced with farther increasing the content of kiln dust-activated coal gangue that replaces clinker, and obviously decreased when content of kiln dust-activated coal gangue is 30%; the performance of resisting sulphate of cement with 30% kiln dust-activated coal gangue is better enhanced; ASR is restrained to some extent.

The binding of sodium and potassium into cement paste influences the performance of concrete: for example, alkali balances between solid and paste constituents and pore fluid affect the potential for alkali aggregates reaction. However, quantification of the binding potential into paste solids has proven to be difficult, although much empirical data are available from pore fluid analyses. In this study, single-phase homogeneous C-S-H phases have been prepared at Ca: Si molar ratios (C/S) of 1.8, 1.6, 1.3, 1.0 and 0.8 and reacted with four alkali hydroxide concentrations, both NaOH and KOH, between 10 and 300 mM. A steady-state alkali partition is attained in less than 4d at 20°C by flame emission spectroscopy and the ξ potential of C-S-H and C-A-S-H gel unreacted and reacted with alkali hydroxide are measured. The results indicate：alkali binding into the C-S-H and C-A-S-H gel improves as its C/S decreases；Al3+ has been introduced to form C-A-S-H gels, and the influence of Al3+ on alkali sorption properties was determined: the replacement of Si4+ by Al3+ and Na+ or k+ markedly increases alkali binding and decreases the ξ potential of gel；the more Ca:Si ratio，the less alkali binding, the more ξ potential of gel.

Microwave-assisted Kornblum oxidation is proved to be an effective way to obtain aldehyde and ketones from their corresponding chlorides. Under microwave irradiation, not only the reaction time was greatly decreased, due to avoiding the by-product, the yield was increased. It is noteworthy that the scope of the method was broadly expanded.

Dry lakes, degraded sandy grasslands, abandoned farmland and mobile dunes which are widely distributed throughout the arid areas of northern China have been investigated in this work. Gain-size distribution of the surface sediments of Manas lake in Junggar basin, Juyan lake in the Alxa plateau, Zhuye lake in Minqin basin and most deserts (such as Mu Us desert, Otindag desert, Horqin desert and Hulun Buir desert) in China have been analyzed. The results show clay with particle sized 60% and ∼50% of the total mass. Since the tiny particles on the surface of abandoned farmland are blown away easily and rapidly, the content of clay particles in Minqin basin is 63 μm and few particles

In this paper, a solvent extraction system is applied to separate the mixture of mandelonitrile (MN) and mandelonitrile acetates (MA) for the first time. The basic consistence of the system is water and n‐hexane with the phase ratio of 1.0. Operation parameters such as temperature, the pH value in the aqueous phase, and the concentration of the mixture and benzaldehyde were investigated to find the optimal conditions. When the temperature was 30°C and the pH value in the aqueous phase was 2.0, a three‐stage extraction was performed. The purity of MA in the organic phase was more than 99% (wt) with the yield of 87.7%. And the purity of MN in the aqueous phase was 98.8 % (wt) with the yield of 92.6%. This extraction system can separate the mixture of MN and MA efficiently.

Aeolian samples from deserts in northern China were studied using the optically stimulated luminescence (OSL) of quartz and potassium (K) feldspar separates. K-feldspar has shown advantages over quartz for dating samples younger than 100 years, due to its more homogeneous equivalent dose ( D e ) values, higher internal dose rate and higher luminescence sensitivity to dose. Without additional measurements, the luminescence characteristics of quartz obtained in D e determination procedures can be used to reveal the source material and/or quartz thermal history for the deserts in northern China. The results indicated that the duration of paleosol formation in desert areas reflects regional paleoenvironments.

In this paper, nine sediment sequences in the inner desert, desert-loess transitional zone (agro-pastoral transitional zone) and the northern margin of the Loess Plateau were investigated to study the sediments of Mu Us (Maowusu) and Otindaq (Hunshandake) sandy land in northern China since the last glaciation. All of these sequences consisted of the upper Holocene dark paleosol and the lower aeolian sand formed during the last glacial stage. The Mu Us and Otindaq sandy land became the active desert since the last glaciation and covered a larger sandy area than at present. Mu Us sandy land began to show a landform of sandy desert and expanded southward towards the northern boundaries of the Loess Plateau. The Holocene was characterized by the advent of warmer and wetter climatic conditions in northern China, resulting in the rapid growth of surface vegetation and Mu Us and Otindaq sandy land became a steppe. The thickness of surface soil reached up to as much as 50–80 cm. Thick paleosol covered the drift sands, and served as a protective layer for the steppe and farmland. Although the last glacial cycle is far away, paleo-aeolian sands formed during that period are still the material sources of regional desertification. Unreasonable cultivation destroying the Holocene paleosol, combined with dry climate and strong wind would result in activation of paleo- aeolian sand leading to the desertification of the study areas.

The purposes of this study are to investigate and analyze the status of reproductive tract infections (RTIs) in married women in rural western China, and to develop effective strategies for improving the ability of married women to prevent RTIs in this region. We conducted in-depth interviews of 142 married women from four villages in three townships. Two questionnaires were used to gather data on married women’s health care status, family income, knowledge about RTIs, relevant behaviors, and attitudes toward RTIs. Descriptive, parallel, and logistic regression analyses and the Chi-square test were applied to analyze the relationships between basic conditions and several influential factors. Over 80% of the respondents were of limited income and had with poor knowledge of and a lack of experience in preventing RTIs. Some 83.3% of the married women had experienced menstrual irregularities; 70.3% of those interviewed had experienced malodorous vaginal discharge with or without perineal itching. It was found that 80.7% of the interviewees did not have good personal hygiene habits in daily living regarding RTIs. It was found that the prevalence of RTIs was lower in women who had accurate information about RTIs. Most married women lacked basic knowledge of ways to prevent RTIs, and this, together with the limited support of the health care system and the absence of medical insurance schemes, was responsible for the observed high prevalence of RTIs. There is an urgent need to improve the capability of married women in rural China to prevent RTIs, and it is important to find effective ways to prevent these diseases. Three health promotion strategies are presently being implemented to prevent RTIs and to build capacity for disease prevention among married women in rural western China.

Molecular characterization of a nucleopolyhedrovirus (NPV) isolated from the diseased larva of Orgyia ericae Germar was firstly analyzed. The genomic size of O. ericae NPV was estimated to be 134.6 kb by restriction endonuclease analysis. The gene encoding the major structural protein, polyhedrin, was cloned and sequenced. Phylogenetic analyses using polyhedrin sequences revealed that O. ericae NPV (OeNPV) was a member of the Group II NPVs and was closely related to the BusuSNPV and OpSNPV cluster. Electron microscopic observations confirmed that OeNPV was a single nucleocapsid type virus (SNPV).

Study of recombinant human interleukin-12 for treatment of complications after radiotherapy for tumor patients

The molecular mechanism for the formation of the P1/P2 blood groups remains unsolved. It has been shown that the P1/P2 polymorphism is connected to the different A4GALT gene expression levels in P1 and P2 red blood cells.The present investigation conducted a pilot investigation that involved the detailed and stepwise screening of single-nucleotide polymorphisms (SNPs) in the A4GALT gene, followed by a larger-scale association study. The transcription-inducing activity by the different genotypes of SNPs was analyzed using reporter assays.A total of 416 different SNP sites in the A4GALT genes from four P1 and four P2 individuals were analyzed in the pilot investigation, and 11 SNP sites, distributed in the A4GALT Intron 1 region, exhibited an association with the P1/P2 phenotypes. In the follow-up association study, the genotypes at the 11 SNPs of a total of 338 individuals across four different ethnic populations were determined, and the results show that two SNPs, rs2143918 and rs5751348, are consistently associated with the P1/P2 phenotypes. Reporter assays demonstrated significantly higher transcription-inducing activity by the SNPs bearing the P(1)-allele genotype than by the SNPs bearing the P(2)-allele genotype and that the difference in transcriptional activity was determined by the different genotypes at SNP rs5751348.The results of this investigation demonstrate a consistent association of A4GALT SNPs rs2143918 and rs5751348 with the P1/P2 phenotypes and suggest that SNP rs5751348 may lead to allelic variations in A4GALT gene expression and consequently leads to the formation of the P1/P2 phenotypes.

Splenic cystic lymphangioma is extremely rare, with very few cases reported until now. Here, we report a case of cystic lymphangioma of the spleen in a young woman who was admitted for evaluation of abdominal pain and a mass lasting for two years. We present this case with emphasis on the problem of differential diagnosis and the difficulties of diagnostic certainty in the absence of histologic features.

The middle and upper reaches of Wenyu River was chosen as a case study area, and the temp-spatial difference of surface water quality was systematically studied by water sampling from June to August of 2009. It was found that distinct seasonal variations was exhibited on surface water quality in the study area. In the mountain regions, TP, TN, NO3(-)-N, NH4(+) -N and TOC concentration in the water increase from June to July, and then decline remarkably, whereas the DO and COD concentration in the water display an opposite pattern. However, in the piedmont plains of Wenyu River middle reaches, TN, TP, PO4(3)-P and COD concentration decrease sharply from June to July and then increase substantially in August, while DO concentration shows a decline tendency from June to August. Furthermore, from the upper stream mountains to middle reaches of Wenyu river, self-purification capacity of surface water is reduced with its nutrient pollution aggravates, and the water pollution process and its formation mechanism are different. Altogether, the process of water pollution in the mountainous areas has a pulse pollution process in the rainy season, and the surface run-off in the rainy season may aggravate the pollution process by bring a large volume of non-point source pollutants into surface water from the land. Because of various types of pollution sources in the piedmont regions, the water pollution processes are unstable and peak surface run-offs in the rainy season may dilute the surface water pollutions. The results provide a scientific basis for ecological function regionalization.

Freshwater ecosystem provides a variety of services to humanity, and in return, human activities give strong stress on the services, particularly in urban area. It is of significance to study the impact of human occupation and stress on freshwater ecosystem. In this paper, a water equivalent method was used to calculate the human occupation on the freshwater ecosystem services in Beijing from 1998 to 2007, and assessed the human stress effect on the freshwater ecosystem, based on the total amount of water resources. In the past 10 years, the water equivalent of human activities in Beijing was about 5 to 17 times larger than the supply of the freshwater ecosystem. The water equivalent of the ecosystem services was decreased in the order of water environment purificationwater resources supplywater habitat maintenancewater safety regulation. The gap between the consumption and the supply of freshwater ecosystem services had a trend of increasing to decreasing from 1998 to 2007, with the largest gap occurred in 1999. This study revealed that there was a huge gap between the consumption and the supply of freshwater ecosystem services in Beijing, which would inevitably result in the overloading occupation of the water resources in the City and give stress to the other regions.

Nitrate pollution in groundwater has become a worldwide problem. It may affect the water quality for daily use and thus the health of people. The temporal and spatial characteristics of nitrate pollution in the groundwater were addressed by sample analysis of the drinkable water from 157 wells in Hailun, Heilongjiang, northeastern China. It was found that the mean value of nitrate concentration in all wells was 14.01 mg x L(-1). Of all the samples, the nitrate concentrations of 26.11% wells exceeded the standard of drinkable water (10.00 mg x L(-1)). A significant difference was found on the spatial distribution of nitrate pollution in the study area. The pollution degree in term of nitrate pollution was in the order: the central rolling hills and flooding plainthe northeastern mountain areathe southwest rolling hills and plain. Based on the results, the factors causing the pollution we analyzed from the well properties and pollution sources. As for well properties, the type of the pipe material plays a critical role in the groundwater nitrate pollution. It was found that the wells with seamless pipe have less pollution than those with multiple-sections pipe. The concentrations of seamless pipe wells and multiple ones were respectively 5.08 mg x L(-1) and 32.57 mg x L(-1), 12.26% and 82.35% of these two kinds wells exceeded 10.00 mg x L(-1), the state drinking water standard. In the whole Hailun, there is no statistically relationship between nitrate-N levels of wells and the well depth. However, a statistically lower nitrate-N was observed in the deep wells than that in the shallower ones. The mean values of nitrate concentration of the seamless-pipe deep wells, seamless-pipe shallow wells, multiple-section-pipe deep wells and multiple-section-pipe shallow wells were 1.84, 12.02, 25.14 and 45.61 mg x L(-1). Analysis of pollution source shows that the heavily polluted regions are usually associated with large use of nitrogen fertilizer and household livestock or poultry. This indicates a positive correlation between the nitrate-N pollution of groundwater and the nitrogen fertilizer, household livestock, poultry.

Scavening effects of panax notoginseng saponins on active oxygen species in the systems of Fenton reaction, autoxidation of pyrogallol and riboflavine photosensitization were investigated by the mean of spectrophotometry. The inhibition of panax notoginseg saponins on the damage of DNA chain induced by hydroxyl radical by panax notoginseng saponins was observed by the mean of gelose gel electrophoresi and thiobartital spectrophotometry. The results showed that panax notoginseng saponins could scaven * OH, O2*- efficiently and protect DNA chains from being damaged by hydroxyl radical.

Microwave-assisted Kornblum oxidation is proved to be an effective way to obtain aldehyde and ketones from their corresponding chlorides. Under microwave irradiation, not only the reaction time was greatly decreased, due to avoiding the by-product, the yield was increased. It is noteworthy that the scope of the method was broadly expanded.

To investigate the effect of the nerve growth factor (NGF), which is isolated and purified from the venom of Naja naja atra, on expression of GAP-43 in dorsal root ganglia (DRG) removed partially from cat.A total of 45 adult male cats (rhizotomy of unilateral L1-Ls, L7-S2 dorsal root, leaving L6 as a spared dorsal root in 45 cats allowed to survive 3 days, 6 days, 12 days respectively) were equally divided into 3 groups based on the dose of using the drug: low-dosage group (1 microg/kg), high-dosage group (2 microg/ kg), normal saline control group (0. 1 mL/kg), with using immunohistochemical reaction to detect the GAP-43 of L6 DRG, count the GAP-43-positive large, medium-small neurons.The results were as follows: After the operation, GAP-43 positive products were mainly distributed in nucleus of large neurons and cytoplasm of medium-small neurons. The expressions of GAP-43 positive products in treatment group and control group were detected at day 3, reached the highest level on the 6th day and began to decrease on the 12th day. The number of GAP-43 positive medium-small neurons of the operated side DRG in treatment group increased more apparently than that of control group, the high-dosage group was significantly (PO. 01) more than that of other groups, especially on day 6, but the number of large neurons did not change prominently.The above results indicate that NGF can effectively induce the synthesis of GAP-43 in medium-small neurons, which enhances the spared root's collateral sprout, the regeneration is related to NGF dosage.

Molecular characterization of a nucleopolyhedrovirus (NPV) isolated from the diseased larva of Orgyia ericae Germar was firstly analyzed. The genomic size of O. ericae NPV was estimated to be 134.6 kb by restriction endonuclease analysis. The gene encoding the major structural protein, polyhedrin, was cloned and sequenced. Phylogenetic analyses using polyhedrin sequences revealed that O. ericae NPV (OeNPV) was a member of the Group II NPVs and was closely related to the BusuSNPV and OpSNPV cluster. Electron microscopic observations confirmed that OeNPV was a single nucleocapsid type virus (SNPV).

The predicted open reading frame of lef-7 from Bombyx mori nucleopolyhedrovirus (BmNPV) is 45 bp longer at the 5'-terminal and harbors a 42 bp deletion towards the 3' terminal end compared to that of Autograph californica mlulticapsid NPV (AcMNPV). In the present study, to determine whether the BmNPV lef-7 is translated from an initiation site different from that of AcMNPV lef-7, the translational and transcriptional initiation sites of BmNPV lef-7 were examined. A BmNPV mutant, Bmlef7M1(-) was constructed by deleting 11 nucleotides (nt) including the predicted initiation codon ATG. Western blot analysis demonstrated that the size of LEF-7 in BmNPV and Bmlef7M1(-)-infected cells was identical. The LEF-7s in BmNPV and Bmlef7M1(-)-infected cells were both localized in the nuclei as observed using confocal microscopy. Therefore, the presumed initiation codon ATG (at 97059 nt of BmNPV genome) appears to be non-functional for lef-7 translation. The 5'-RACE analysis revealed that transcription of lef-7 mRNA in BmNPV and Bmlef7M1(-)-infected cells both initiated from an ATCATT motif located 26 nt upstream of the second ATG (located at 97014 nt on BmNPV genome), and 20 nt downstream of the presumed initiation codon.

To investigate the effects of Taohong Siwu decoction II on B16 melanoma in mice and the underlying mechanism.C57BL/6J mice bearing B16 melanoma were used in this study. The experimental groups were treated respectively with Taohong Siwu decoction II at doses of 2.5, 5 and 10 g x kg(-1) and cyclophosphamide at 0.05 g x kg(-1), Taohong Siwu decoction II at 10 g x kg(-1) plus cyclophosphamide at 0.025 mg x kg(-1). The tumor volume and weight, the expression of VEGF and KDR/FLK-1 and the amount of MVD were measured.The tumor volume and weight, the expression of VEGF and KDR/FLK-1 and the amount of MVD were reduced significantly after treatment with Taohong Siwu decoction II at the doses of 5 and 10 g x kg(-1) and Taohong Siwu decoction II combined with cyclophosphamide as compared with normal saline-treated group (P0.01).Taohong Siwu decoction II can inhibit the growth of B16 melanoma in mice and attenuate the expressions of VEGF and KDR/FLK-1, suggesting that Taohong Siwu decoction II produces the antitumor effect via a possible antiagiogenisis mechanism.

(R)-chlorprenaline, a selective activator of beta2 receptor and an effective drug for bronchitis and asthma, is industrially prepared from (R)-2'-chloro-1-phenyl-ethanol. In this communication, we describe (1) the identification of Saccharomyces cerevisiae B5 as an effective host for stereoselective reduction of 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol; (2) the presence of ethanol enhances the conversion; and (3) the biochemical factors that effect the yield of the product. Among the four yeast strains capable of reduction 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol we screened, Saccharomyces cerevisiae B5 showed the highest activity and stereoselectivity, and was used for the subsequent study. The effect of the presence of methanol, ethanol, 2-propanol, 1-butanol, glucose, glycerol and lactic acid was first investigated, as it was previously reported that they increased the yield and stereoselectivity of the reaction. The addition of the co-substrate methanol, ethanol, 2-propanol, 1-butanol, glucose and glycerol favored the formation of the 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol. Lactic acid inhibited the enzyme activity. Ethanol is the best co-substrate among the seven co-substrates and under the optimum concentration of 5% , the yield of (R)-2'-chloro-1-phenyl-ethanol was increased from 17% to 74%. The oxidation of ethanol regenerates NADH required for the reduction. The effects of the reaction time, pH, cell concentration, substrate concentration and temperature on the reduction were investigated next. The enantiometric excess of (R)-2'-chloro-1-phenyl-ethanol reached 100% under the optimal condition: pH8.0, 25 degrees C and 5% ethanol. The product yield went up with the increasing Saccharomyces cerevisiae B5 concentration and reached 100% when the cell dry weight was 10.75 mg/mL and 2'-chloroacetophenone was 6.47 mmol/L. The yield of (R)-2'-chloro-1-phenyl-ethanol decreased sharply with the increase of substrate concentration, as the high concentration of substrates is toxic to the cell and inhibits the activity of reductases. The aerobic cultivation of the yeast and shaking during the reaction increased the yield of (R)-2'-chloro-1-phenyl-ethanol. The yeast can be reused up to 15 times. This research paves the way for economical preparation of chiral 2'-chloroacetophenone to R-2'-chloro-1-phenylethanol.

Water activities of poly(ethylene glycol) (PEG) + salt + H2O systems have been measured using an improved isopiestic method at 25 °C. The salts used were MgSO4, (NH4)2SO4, KH2PO4, and K2HPO4. The water activities were correlated successfully with an empirical equation.

A gas chromatographic method was developed to directly determine the enantiomers of acrylic ketone alcohol and acrylic ketone acetate. Two pairs of enantiomers were nearly baseline-separated by using Model HP-5890 Gas Chromatograph with flame ionization detector and WCOT CD-Chiral-DEX CB (30 m x 0.25 mm i.d.) column. The optimum conditions were the split ratio of 30:1 for the sample injected, the flow rates of 3.7 mL/min for the carrier gas (nitrogen), 60 mL/min for the hydrogen, and 250 mL/min for the oxygen, and temperatures of 148 degrees C for the column, 230 degrees C for the injector, and 230 degrees C for the detector. The linearity and reproducibility were satisfactory. The regression coefficients were over 0.9965. The RSDs obtained were less than 1.25%. The method was further used to trace the reactants and products, and to evaluate the enzyme catalyst activity and selectivity under different conditions. The results show that the method developed is very successful.