高浓度氧处理法阻断蚕卵滞育

【目的】比较高浓度氧处理法(高氧法)与传统HCl处理法(HCl法)阻断蚕卵滞育效果的差异,探讨高氧法阻断滞育在家蚕Bombyx mori转基因技术体系上的应用。【方法】采用高氧法和HCl法在产后20 h处理二化性蚕品种‘大造’,比较孵化率、孵化时间,调查高氧法的最佳处理条件;将高氧法应用于一化性蚕品种‘土耳其’和转基因二化性蚕品种‘大造’,调查其对一化性蚕品种蚕卵阻断滞育效果及转基因二化性蚕品种显微注射后蚕卵阻断滞育效果。【结果】高氧法对二化性蚕卵在孵化率、孵化时间上都与HCl法有相近的阻断滞育的效果,其最佳条件为产卵后20 h用体积分数为70%的O2处理40 h;该方法也能成功阻断一化性蚕品种,孵化率达(71±20)%;高氧法处理的显微注射转基因家蚕卵孵化率达到了(49±9)%,而对照组的孵化率为0。【结论】高氧法为今后生产上替代HCl法,采用安全环保的蚕卵阻断滞育技术,解决转基因蚕卵阻断滞育和提高转基因家蚕育种进度的关键问题提供了可行的新方法。

高剂量左氧氟沙星序贯法治疗呼吸道感染疗效探讨

目的:研究分析高剂量左氧氟沙星序贯法治疗呼吸道感染的临床效果。方法:选取63例呼吸道感染患者的临床资料,将其随机分为治疗组和对照组,治疗组32例患者采用高剂量左氧氟沙星序贯法进行治疗,对照组31例患者采用头孢他啶治疗,对比分析两组患者的临床治疗效果。结果:治疗组患者总有效率为87.5%,对照组患者总有效率为80.6%,两组患者疗效对比,有显著性差异(P<0.01)。结论:高剂量左氧氟沙星序贯法治疗呼吸道感染疗效显著、安全,值得推广。

120 t复吹转炉高拉碳低磷出钢的冶炼工艺改进

转炉冶炼重轨钢、轴承钢等高碳钢,氧枪控制采用传统低-高-低三段式冶炼模式,因前期石灰难以熔化、中期喷溅加剧、后期失去高碱度脱磷机会,造成冶炼过程喷溅率高、终点拉碳合格率低等问题。为解决此问题,通过冶炼工艺分析,采用改进后的氧枪控制为高-低-低-高-低五段式新冶炼模式。其综合结果为冶炼过程喷溅率明显降低,喷溅率由20%~30%降低到15%以下;终点拉碳合格率大幅提升,终点拉碳合格率由69.06%提高到93.55%。

High temperature oxidation resistance and microstructure change of aluminized coating on copper substrate

The outermost coating with single phase Ni2Al3 was obtained on copper surface by electrodepositing nickel followed by slurry pack aluminizing at 800 °C for 12 h. The oxidation resistance and microstructure of the coating oxidized in ambient air at 1000 °C for 25-250 h were investigated using SEM, X-ray diffraction and optical microscope methods. The results show that the copper with single phase Ni2Al3 coating possesses the best high temperature oxidation resistance, and the mass gain of the coating is 1/15 that of pure copper and 1/2 that of nickel coating, respectively. The specimen surface after being oxidized for 25 h still comprises Ni2Al3 phase. However, when the time of oxidizing treatment increases to 50 h, the Ni Al phase is formed. It is also found that the Ni2Al3 phase completely turns into Ni Al phase after oxidizing treatment for 100 h and above. The Ni Al coating shows excellent high temperature oxidation resistance when oxidation time is 250 h.

Research into Uncertainty in Measurement of Seawater Chemical Oxygen Demand by Potassium Iodide-Alkaline Potassium Permanganate Determination Method

Using the glucose and L-glutamic-acid to prepare the standard substance according to the ratio of 1：1, and the artificial seawater and the standard substance to prepare a series of standard solutions, the distribution pattern of uncertainty in measurement of seawater COD is obtained based on the measured results of the series of standard solutions by the potassium iodide-alkaline potassium permanganate determination method. The distribution pattern is as follows： Uncertainty in measurement is big and not constant at the high end, but small and constant at the low end.

Preliminary Studies on High-performance Liquid Chro-matography Chemiluminescence Determination of theSaturated Fatty Acids(C_(16) C_(18))in Human Serum

The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture of chloroform-n-heptane.2-(4-Hydrazinocarbonyl- phenyl)-4,5-diphenylimidazole (HCPI) was used as a fluorescent labelling reagent of the fatty acids. The labelling reaction was carried out at 30℃ for 1 h at pH 6.5 and the resulting reaction mixture was sudjected to HPLC. The labelled fatty acid C_(17)(P-C_(17))was used as the internal standard. The la- belled fatty acids C_(16) and C_(18) were separated within 18 min on an ODS-8OTM column (150 mm× 6 mm ID,5μm,Tosoh Japan).The calibrlation curves of fatty acids from the spiked control serum were Y_1=-0.003 7 + 0.0028X_1,r=0.994 for FA C_( 16) and Y_2=0.00 1 2 + 0.00098X_2,r=0.999 for FA C_( 18),respectively.The average recoveries of facids from the spiked contrl serum were 107.2%(n=8,RSD=4.3%)for FA C_(16) and 97.35%(n=8, RSD=4.0%)for FA C_(18),respectively.The lower detection limits of fatty acids after reaction were 12μmol per 20μl injection for FA C_(16) and 18 μmol per 20μl injection for FA C_(18),respectively(signal to noise ratio, S/N=2).The HPLC/CL method was applied to the determination of FA C_(16) and FA C_(18) in normal human serum and the results showed that the concentrations of fatty acids in normal human serum were 0.134 ± 0.009 μ mol/ml serum(n=5) for FA C_(16) and 0.052±0.028 μmol/ml serum(n=5)for FA C_(18),respectively.

Combination of allopurinol and hyperbaric oxygen therapy:A new treatment in experimental acute necrotizing pancreatitis?

AIM： To investigate the individual and combined effects of allopurinol and hyperbaric oxygen （HBO） therapy on biochemical and histopathological changes, oxidative stress, and bacterial translocation （BT） in the experimental rat acute pancreatitis （AP）. METHODS： Eighty-five Sprague-Dawley rats were included in the study. Fifteen of the eighty-five rats were used as controls （sham, Group I ）. AP was induced via intraductal taurocholate infusion in the remaining seventy rats. Rats that survived to induction of acute necrotizing pancreatitis were randomized into four groups. Group H received saline, Group m allopurinol, Group IV allopurinol plus HBO and Group v HBO alone. Serum amylase levels, oxidative stress parameters, BT and histopathologic scores were determined. RESULTS： Serum amylase levels were lower in Groups Ⅲ, Ⅳ and v compared to Group H （974 ± 110, 384 ± 40, 851 ＋ 56, and 1664 Ⅳ 234 U/L, respectively, P 〈 0.05, for all）. Combining the two treatment optionsrevealed significantly lower median [25-75 percentiles] histopathological scores when compared to individual administrations （13 [12.5-15] in allopurinol group, 9.5 [7-11.75] in HBO group, and 6 [4.5-7.5] in combined group, P 〈 0.01）. Oxidative stress markers were significantly better in all treatment groups compared to the controls. Bacterial translocation into the pancreas and mesenteric lymph nodes was lower in Groups m, iV and v compared to Group H （54%, 23%, 50% vs 100% for translocation to pancreas, and 62%, 46%, 58% vs 100% for translocation to mesenteric lymph nodes, respectively, P 〈 0.05 for all）. CONCLUSION： The present study confirms the benefit of HBO and allopurinol treatment when administered separately in experimental rat AP. Combination of these treatment options appears to prevent progression of pancreatic injury parameters more effectively.

Changes of Clay Mineral Association After High-Gradient Magnetic Separation

The changes of clay mineral association after high-gradient magnetic separation (HGMS) treatment, and the effects of chemical and physical technologies on concentrating Fe oxides for main soils in central and southern China were investigated by means of X-ray diffraction (XRD) and chemical analysis methods. Results indicated that the concentrating times of Fe oxides by HGMS treatment were the largest for 0.2-2 μmsize fractions in the examined soils. For the soils in which 2: 1 phyllosilicates were dominant, concentrating times of iron oxides by HGMS treatment were larger than by 5 mol L-1 NaOH treatment. Phyllosili-cates were decreased after HGMS treatment; however, the decrease was less than that of kaorolinite. The goet bite / (goethite + hematie) values in Fe oxides of the soils kept virtually constant after HGMSt reatment.

High-flow nasal oxygen availability for sedation decreases the use of general anesthesia during endoscopic retrograde cholangiopancreatography and endoscopic ultrasound

AIM To examine whether high-flow nasal oxygen(HFNO) availability influences the use of general anesthesia(GA) in patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) and endoscopic ultrasound(EUS) and associated outcomes.METHODS In this retrospective study, patients were stratified into 3 eras between October 1, 2013 and June 30, 2014 based on HFNO availability for deep sedation at the time of their endoscopy. During the first and last 3-mo eras(era 1 and 3), no HFNO was available, whereas it was an option during the second 3-mo era(era 2). The primary outcome was the percent utilization of GA vs deep sedation in each period. Secondary outcomes included oxygen saturation nadir during sedation between periods, as well as procedure duration, and anesthesia-only time between periods and for GA vs sedation cases respectively.RESULTS During the study period 238 ERCP or EUS cases were identified for analysis. Statistical testing was employed and a P < 0.050 was significant unless the Bonferroni correction for multiple comparisons was used. General anesthesia use was significantly lower in era 2 compared to era 1 with the same trend between era 2 and 3(P = 0.012 and 0.045 respectively). The oxygen saturation nadir during sedation was significantly higher in era 2 compared to era 3(P < 0.001) but not between eras 1 and 2(P = 0.028) or 1 and 3(P = 0.069). The procedure time within each era was significantly longer under GA compared to deep sedation(P ≤ 0.007) as was the anesthesia-only time(P ≤ 0.001).CONCLUSION High-flow nasal oxygen availability was associated with decreased GA utilization and improved oxygenation for ERCP and EUS during sedation.

Determination of Sulphonamide Antibiotics and Trimethoprim in Wastewater and Sludge Using Liquid Chromatography with Diode-Array Detection

This paper investigates the occurrence of sulphonamide and diaminopyrimidine antibiotics in wastewater and sludge from wastewater treatment plants. In our experiment, they were isolated from wastewater using the solid phase extraction method. In the case of sludge, pressurized solvent extraction techniques were used followed by solid phase extraction. The solid phase extraction method was used for purification and concentration. Sulphonamide and diaminopyrimidine antibiotics were determined using high performance liquid chromatography with diode-array detection. The selected antibiotics were determined in real sludge samples collected from the wastewater treatment plant in Brno-Mod^ice and in real wastewater samples collected from the wastewater treatment plant located on the grounds of the University of Veterinary and Pharmaceutical Sciences in Brno, using the developed and optimized method. Analyses showed that real samples of wastewater contained sulphathiazole 11.82μg/L at the inflow （7.1 μg/L at the outflow）, sulphapyridine 18.57 I.tg/L （12.2 μg/L）, sulphamethazine 13.52 μg/L （8.44 μg/L）, sulphamethoxazole 14.06 lag/L （9.34 Ixg/L） and trimethoprim 521.4 lag/L （422.29 μg/L）. Here it is demonstrated that drugs are removed through the wastewater treatment procedure only partially.

不同密闭式吸痰方法在ARDS患者中的应用比较

目的:探讨密闭式吸痰时高氧疗和/或肺泡复张术对急性呼吸窘迫综合征(ARDS)患者吸痰后的应用和影响。方法:建立人工气道行机械通气的ARDS患者42例,随机分为研究组和对照组各21例,对照组采用高氧法密闭式吸痰即吸痰时高氧供吸痰前1 min给予100%氧供并贯穿整个吸痰过程共持续2 min(高氧法);研究组采用高氧-复张法(结合法)即采用高氧法与复张法密闭式吸痰方法吸痰,复张法即吸痰后即刻调节PEEP水平到2.0 kPa(20 cm H2O),通气10 s。观察吸痰前1 min、吸痰后1、3 min患者呼吸力学及血气的变化,并记录两组患者的机械通气时间、气压伤、肺不张和肺部感染的发生率。结果:两组患者吸痰前血流动力学、动脉血气、呼吸力学各参数比较,均无显著性差异(P>0.05),吸痰后除心率变化无显著性差异外(P>0.05),其余各项指标、两组机械通气时间、肺不张和肺部感染发生率差异均有显著性(P<0.05)。高氧法吸痰后1 min PaO2、SaO2较基线水平有所升高,结合法吸痰后3 min PaO2、SaO2升高(P<0.05)。结论:高氧法可短暂改善密闭式吸痰所引起的缺氧,对ARDS机械通气患者给予结合法吸痰能够保持吸痰前后全过程较好氧合状态,纠正吸痰所导致的低氧,改善肺的顺应性,并能缩短机械通气时间、降低肺不张和肺部感染发生率。

Preparation of Surfactant-Free Pt and PtRu Nanoparticles with High Activity for Methanol Oxidation

A simple and green approach to synthesize highly active electro-catalysts for methanol oxi- dation reaction （MOR） without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cleaned and pre-oxidized multiwall carbon nanotubes （MWC- NTs） from Pt salt by using CO as the reductant. MOR activity has been characterized by both cyclic voltammetry and chronoamperometry, the current density and mass specific current at the peak potential （ca. 0.9 V vs. RHE） reaches 11.6 mA/cm^2 and 860 mA/mgpt, respectively. After electro-deposition of Ru onto the Pt/MWCNTs surface, the catalysts show steady state mass specific current of 20 and 80 mA/mgpt at 0.5 and 0.6 V, respectively.

Phenol Oxidation by Combined Cavitation Water Jet and Hydrogen Peroxide

The paper presents results of phenol oxidized under the conditions of high temperature created during collapse of cavitation bubbles.The degradation efficiency has been greatly improved by using cavitation water jets combined with H2O2 as demonstrated in laboratory tests.Various factors affecting phenol removal ratio were ex-amined and the degradation mechanism was revealed by high performance liquid chromatography(HPLC).The re-sults showed that 99.85% of phenol was mineralized when phenol concentration was 100 mg·L-1 with pH value of 3.0,H2O2 concentration of 300 mg·L-1,confining pressure of 0.5 MPa,and pumping pressure of 20 MPa.The in-termediate products after phenol oxidation were composed of catechol,hydroquinone and p-benzoquinone.Finally,phenol was degraded into maleic acid and acetic acid.Furthermore,a dynamic model of phenol oxidation via cavi-tation water jets combined with H2O2 has been developed.

Biodegradation of Acid Anthraquinone Dye in a Facultative-aerobic Process:Kinetics and Products

The transformation of an anthraquinone dye blue 324 in a facultative-aerobic(F-A) system was investigated.Kinetic parameter study showed that higher Vmax coupled with more recalcitrant chemical oxygen demand(COD) were found in the facultative biofilm reactor(FBR) than in the aerobic reactor(AR).Results of the product analyses indicated that most of dye molecular could be facultatively broken down into simple intermediates,which would be further degraded under subsequent aerobic condition.The main metabolites in each reactor were detected by infrared(FT-IR) and high performance liquid chromatography and mass spectrometry(HPLC-MS).Comparison of the toxicities among the dye and its metabolites was conducted,surprisingly,the colorless intermediates from FBR possessed less inhibitory than original dye and the median effective luminescence concentration(EC50) in 15 min for aerobic effluent could not be detected,showing that hardly toxic products existed in the aerobic process effluent.

Degradation of Antibiotics in Aqueous Solution by Photocatalytic Process： Comparing the Efficiency in the Use of ZnO or TiO2

The study examined the photodegradative efficiency of ZnO and TiO2 in degradation of antibiotics in aqueous matrices. Among several types of antibiotics, four antibiotics were chosen to feature the major classes of these compounds： amoxicillin, erythromycin, streptomycin and ciprofloxacin. Degradation of antibiotic solutions was carried out mainly under UV-light irradiation in a set time with the presence of small quantity of zinc oxide or titanium dioxide. Solutions were analyzed with HPLC chromatography and degradation percentages were calculated from ratio between pick area associated to no degraded drug solution and degraded drug solution＇s pick area. Meanwhile, toxicity of antibiotics and degrading compounds were investigated using a biosensor system, consisting of Clark＇s electrode associated with a portion of agar medium culture containing Saccharomyces Cerevisiae yeast cells. This way, it was possible to define the oxygen that was consumed by yeast cells. Toxicity associated to antibiotics and degrading products are related to decrease of oxygen concentration in solution. It is clear that zinc oxide is slower than titanium dioxide to degrade antibiotics, but zinc oxide shows better photodegradation efficiency than titanium dioxide in spite of its small specific superficial area.

Synthesis of Macro-Mesostructured γ-Al_2O_3 with Large Pore Volume and High Surface Area by a Facile Secondary Reforming Method

Through improving the aging process during synthesis of the support, γ-Al2O3 with large pore volume and high surface area was synthesized by a facile secondary reforming method. The synthesis parameters, such as the reaction temperature, the first aging temperature and the second aging temperature, were investigated. The textural properties of γ-Al2O3 were characterized by means of N2 adsorption-desorption isotherms, X-ray powder diffractometry （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared （FTIR） spectroscopy and thermogravimetry （TG）. The experimental results indicated that AACH and amorphous A1OOH were the precursors of alumina, which were formed via precipitation from solutions after reaction of aluminum sulphate with ammonium hydrogen carbonate. The precursor nanocrystallites grew and re-assembled during the secondary reforming process, which resulted in an increased pore size and pore volume and a decreased bulk density. The as-synthesized γ-Al2O3 materials featured meso/macroporosity, large pore volume （2.175 cm^3/g）, high surface area （237.8 m^2/g）, and low bulk density （0.284 g/mL）.

Lignin in Marine Environment and Its Analysis-A Review

Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial organic carbon(TOC) in marine environment since the 1970s.Lignin polymers are not amenable to direct chemical analysis without prior isolation.This review focused on the methods of chemical decomposition,extraction,derivatization and detection of lignin in marine environment.We described and compared several chemical decomposition methods,including nitrobenzene oxidation,alkaline cupric oxide(CuO) oxidation and thermochemolysis,and detection methods such as gas chromatography(GC),gas chromatography-mass spectrometry(GC-MS),high performance liquid chromatography(HPLC) and so on.Possible improvement of lignin analysis and the application prospects of this tracer were also discussed.

Catalytic Decomposition of Chlorophenols Using Fiber-supported Cobalt Phthalocyanine

A novel heterogeneous catalyst, viscose fiber- supported cobalt phthalocyanine （Co - TDTAPc - F）, was prepared by immobilizing cobalt tetra（2.4 - dichloro- 1,3, 5 -triazine）aminophtbalocyanine （Co- TDTAPc） on viscose fibers covalcntly. The oxidative removal of chlorophenols such as 2 - chlorophenoi, 4 - chlorophenol, 2, 4 - dichlorophenol, and 2, 4, 6 - trichlorophenol was investigated in the catalytic oxidative system of Co - TDTAPc- F/H2O2. Furthermore, more than 98% of these chloropbenols were decomposed in 4 h. Phenol, oxalic acid, maleic acid, and succinic acid, etc., were detected by high performance liquid chromatography （HPLC） and gas chromatography-mass spectrophotometer （GC - MS）, and these short-chain organic acids could be further oxidized easily. The results indicated that the catalytic oxidation in the Co- TDTAPc - F/H2O2 system leaded to a deeper oxidation. In addition, a degradation pathway for chlorophenols was proposed on the basis of detection of intermediate compounds.

Removal of Pharmaceutically Active Compounds in Sequencing Batch Reactor

Biological treatment efficiency of six pharmaceutical compounds （acetazolamide, metronidazole, opipramol, piracetam, salicylamide and tinidazole） was evaluated using lab-scale Sequencing Batch Reactor （SBR）. Comparative biological degradation processes of two types of activated sludge from municipal and pharmaceutical industry sewage treatment plants were examined. Three different organic loadings （0.05 g COD/g MLSS.d, 0.1 g COD/g MLSS.d and 0.2 g COD/g MLSS-d） and reaction time on the efficiency of Active Pharmaceutical Ingredient （API） decomposition were examined. Chemical oxygen demand, non-purgeable organic carbon as well as ammonium nitrogen contents were monitored by standard methods. Percentage of API decomposition was analysed by High Performance Liquid Chromatography （HPLC）. The overall API removal efficiency was strictly dependent on the type of activated sludge origin. The main biodegradation products were identified using HPLC-MS,1H NMR and 13C NMR methods as e.g. （{4-[3-（5H-dibenzo[b,f]azepin-5-yl]piperazin-l-yl}methanamine） and （2-amino-1,3,4-thiadiazol-5-sulfonamide） for opipramol and acetazolamide respectively.