兰州沙尘总悬浮微粒中有机污染物的变化及来源

比较了2006年春季沙尘天气和非沙尘天气吸附到TSP样品中增塑剂、正构烷烃、多环芳烃(PAHs)、甾烷和藿烷类等有机污染组分特征.显示兰州TSP中增塑剂等的工业污染相当严重,煤和生物质燃烧排放以及交通排放较高.非沙尘天气时,污染物主体主要来源于交通排放藿烷和化石燃料燃烧产物释放(煤和生物质燃烧排放为主)的PAHs;而沙尘天气时,虽然兰州地区气体颗粒物急剧增多,但由于有机污染物被沙尘暴带到东部地区,这些有机物质量分数都明显降低.在非沙尘天气,可能是由于沙尘暴源区和沿途土壤高等植物蜡质的风成输入,生物来源的正构烷烃贡献相对增加,其中5个oxy-PAHs和邻苯二甲酸二异壬酯在大气环境研究中很少报道.

小花棘豆(Oxytripis glabra DC)毒素基因的cDNA克隆及序列测定

在完成小花棘豆毒素 95 %氨基酸序列的基础上 ,根椐已知的氨基酸序列 ,设计合成了特异简并引物 .以小花棘豆总RNA为模板 ,逆转录合成cDNA第一链 ,用置换法合成双链cDNA .用特异引物对此双链cDNA进行PCR扩增 ,将扩增后的目的基因与用SmaⅠ酶切的质粒pUC 18连接 ,转化大肠杆菌JM10 7.筛选阳性克隆进行序列分析 ,获得了OXY基因的全部序列 .经测序后测得基因序列与原氨基酸序列对照完全一致 .GenBnak数据检索说明 ,OXY基因编码序列确定是一个从未报道的序列 .此研究结果对该毒素的应用研究奠定了基础 .

棕榈花蕾提取物对大鼠离体子宫平滑肌的作用

目的 探讨棕榈花蕾三种不同提取物对子宫平滑肌的作用。方法 采用BL— 4 10生物机能实验系统 ,测量三种提取物对大鼠离体子宫平滑肌及在缩宫素作用下子宫平滑肌收缩频率、收缩幅度和活动力。结果 棕榈花蕾提取物使大鼠离体子宫平滑肌的收缩频率增快、收缩幅度降低、而张力提高。对缩宫素所致离体子宫收缩有抑制作用。结论 棕榈花蕾提取物对大鼠离体子宫平滑肌有直接兴奋作用。

Identifying the optimal HVOF spray parameters to attain minimum porosity and maximum hardness in iron based amorphous metallic coatings

Flow based Erosion e corrosion problems are very common in fluid handling equipments such as propellers, impellers, pumps in warships, submarine. Though there are many coating materials available to combat erosionecorrosion damage in the above components, iron based amorphous coatings are considered to be more effective to combat erosionecorrosion problems. High velocity oxy-fuel(HVOF)spray process is considered to be a better process to coat the iron based amorphous powders. In this investigation, iron based amorphous metallic coating was developed on 316 stainless steel substrate using HVOF spray technique. Empirical relationships were developed to predict the porosity and micro hardness of iron based amorphous coating incorporating HVOF spray parameters such as oxygen flow rate, fuel flow rate, powder feed rate, carrier gas flow rate, and spray distance. Response surface methodology(RSM) was used to identify the optimal HVOF spray parameters to attain coating with minimum porosity and maximum hardness.

Microstructural analysis and hot corrosion behavior of HVOF-sprayed Ni–22Cr–10Al–1Y and Ni–22Cr–10Al–1Y–SiC(N) coatings on ASTM-SA213-T22 steel

The present paper deals with the investigation of microstructure and high-temperature hot corrosion behavior of high-velocity oxy fuel(HVOF)-produced coatings. Two powder coating compositions, namely, Ni22Cr10Al1Y alloy powder and Ni22Cr10Al1Y(80 wt%;microsized)–silicon carbide(SiC)(20 wt%;nano(N)) powder, were deposited on a T-22 boiler tube steel. The hot corrosion behavior of bare and coated steels was tested at 900°C for 50 cycles in Na2SO4–60 wt%V2O5 molten-salt environment. The kinetics of corrosion was established with weight change measurements after each cycle. The microporosity and microhardness of the as-coated samples have been reported. The X-ray diffraction,field emission-scanning electron microscopy/energy dispersive spectroscopy, and X-ray mapping characterization techniques have been utilized for structural analysis of the as-coated and hot-corroded samples. The results showed that both coatings were deposited with a porosity less than2%. Both coated samples revealed the development of harder surfaces than the substrate. During hot corrosion testing, the bare T22 steel showed an accelerated corrosion in comparison with its coated counterparts. The HVOF-sprayed coatings were befitted effectively by maintaining their adherence during testing. The Ni22Cr10Al1Y–20 wt%SiC(N) composite coating was more effective than the Ni–22Cr–10Al–1Y coating against corrosion in the high-temperature fluxing process.

Boosting overall water splitting by incorporating sulfur into NiFe(oxy)hydroxide

Developing highly active and cost-effective electrocatalysts for enhancing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is a significant challenge for overall water splitting.Sulfur-incorporated nickel iron(oxy)hydroxide(S-NiFeOOH)nanosheets were directly grown on commercial nickel foam using a galvanic corrosion method and a hydrothermal method.The incorporation of sulfur into NiFeOOH enhanced the catalytic activity for the HER and OER in 1 M KOH electrolyte.The enhanced catalytic activity is attributed to the change in the local structure and chemical states due to the incorporation of sulfur.High performance for overall water splitting was achieved with an alkaline water electrolyzer.This was realized by employing S-NiFeOOH as a bifunctional electrocatalyst,thereby outperforming a water electrolyzer that requires the usage of precious metal electrocatalysts(i.e.,Pt/C as the HER electrocatalyst and IrO_(2) as the OER electrocatalyst).Moreover,when driven by a commercial silicon solar cell,an alkaline water electrolyzer that uses S-NiFeOOH as a bifunctional electrocatalyst generated hydrogen under natural illumination.This study shows that S-NiFeOOH is a promising candidate for a large-scale industrial implementation of hydrogen production for overall water splitting because of its low cost,high activity,and durability.In addition,the solar-driven water electrolyzer using S-NiFeOOH as a bifunctional electrocatalyst affords the opportunity for developing effective and feasible solar power systems in the future.

Synthesis and Crystal Structure of N-((3-(2-nitrophenyl) propanoyl)oxy)-N-phenylbenzamide

The title compound N-（（3-（2-nitrophenyl） propanoyl）oxy）-N-phenylbenzamide（C22H18N2O5,Mr = 390.38） was synthesized with nitrobenzene as the starting materials and structurally characterized by 1H NMR,13 C NMR,IR,H RMS（E-SI） and single-crystal X-ray diffraction.The crystalline structure of the title compound was studied in detail.The single-crystal X-ray diffraction revealed that the compound crystallizes in monoclinic,space group P21/n,with a = 14.4481（7）,b = 8.0089（5）,c = 16.6808（9） A,α = 90.00（5）,β = 100.069（5）,γ = 90.00（5）°,Mr = 390.38,V = 1900.46（18） A^3,Z = 4,Dc = 1.364 g/cm^-3,μ = 0.098,F（000） = 816.0,the final R = 0.0530 and w R = 0.1141 for 2525 observed reflections（I 〉 2σ（I））,R（all data） = 0.0813,w R（all data） = 0.1335,completeness to theta of 26.020 is 99.8% and GOF = 1.085.The crystal structure contains three branched chains with its center placed at the midpoint of N.The phenyl ring（C（8）~C（13）） makes a dihedral angle of 83.5（1） ℃ with the phenyl ring（C（1）~C（6））,and 80.5（1） ℃with the nitro-substituted benzene ring（C（17）~C（22））,indicating that the three rings are not coplanar.Hydrogen bonds（C（10）–H（10）···O（3））,（C（15）–H（15B）···O（4） and C（16）–H（16B）···O（4）） together with π-π stacking interactions stabilize the structure of the molecule.The preliminary biological test shows that the title compound has good antitumor activity against A549 in vitro with the IC50 value of 3.17 μmol.

Chelation-mediated in-situ formation of ultrathin cobalt(oxy)hydroxides on hematite photoanode towards enhanced photoelectrochemical water oxidation

In this work,a facile chelation-mediated route was developed to fabricate ultrathin cobalt(oxy)hydroxides(CoOOH)nanosheets on hematite photoanode(Fe_(2)O_(3)).The route contains two steps of the adsorption of[Co-EDTA]^(2-)species on Fe_(2)O_(3) nanorod array followed by the hydrolysis in alkaline solution.The resulting CoOOH/Fe_(2)O_(3) exhibits a remarkably improved photocurrent density of 2.10 mA cm^(-2) at 1.23 V vs.RHE,which is ca.2.8 times that of bare Fe_(2)O_(3).In addition,a negative shift of onset potential ca.200 mV is achieved.The structural characterizations reveal the chelate EDTA plays important roles that enhance the adsorption of Co species and the formation of contact between CoOOH and Fe_(2)O_(3).(Photo)electrochemical analysis suggests,besides providing active sites for water oxidation,CoOOH at large extent promotes the charge separation and the charge transfer via passivating surface states and suppressing charge recombination.It also found CoOOH possesses some oxygen vacancies,which could act as trapping centers for photogenerated holes and facilitate the charge separation.Intensity modulated photocurrent spectroscopy(IMPS)shows that,under low applied potential the water oxidation mainly occurs on CoOOH,while under high applied potential the water oxidation could occur on both CoOOH and Fe_(2)O_(3).The findings not only provide an efficient strategy for designing ultrathin(oxy)hydroxides on semiconductors for PEC applications but also put forward a new insight on the role of CoOOH during water oxidation.

D-Ser2-Oxyntomodulin改善Aβ31-35所致小鼠昼夜节律紊乱

目的:观察胃泌酸调节素类似物D-Ser2-Oxyntomodulin(Oxy)是否可以改善β淀粉样蛋白31-35(Aβ31-35)所致的小鼠昼夜节律紊乱,探讨Oxy改善Aβ31-35所致昼夜节律紊乱的细胞分子机制。方法:(1)选取6~8周龄C57BL/6雄性小鼠进行跑轮行为学实验,分析Oxy改善Aβ31-35所致小鼠昼夜节律紊乱的作用。(2)选取小鼠海马HT22神经细胞,CCK8法检测细胞存活率,Real-time PCR检测不同时间点钟基因Bmal1和Per2 mRNA的变化趋势,Western Blot分别检测CT20时Bmal1蛋白和CT16时Per2蛋白的表达情况。结果:(1)Aβ31-35引起小鼠昼夜节律紊乱,与对照组相比,自由运转周期显著延长。Oxy预处理再给予Aβ31-35后小鼠的昼夜节律紊乱情况有所改善,与Aβ单独给予相比,自由运转周期显著降低。(2)Aβ31-35引起HT22细胞存活率显著降低,Oxy预处理后有效逆转Aβ31-35诱导的细胞存活率下降,且具有剂量依赖性。(3)经Aβ31-35处理后,HT22细胞的Bmal1和Per2 mRNA水平分别在CT20和CT16较对照组明显降低;而Oxy预处理组Bmal1和Per2的异常表达均得到显著改善。(4)与对照组相比,Aβ31-35组CT20时Bmal1和CT16时Per2蛋白水平显著降低;而与Aβ31-35组相比,Oxy预处理组Bmal1和Per2蛋白水平有所升高。结论:Oxy可能通过调整Bmal1和Per2的表达改善Aβ31-35所致C57BL/6小鼠昼夜节律紊乱。

Crystal Structures and Antibacterial Activities of 1,3-Phenylenebis(oxy)diacetic Acid Dihydrate and 4,4'-Bipyridine Cocrystal

Single crystals of two 1,3-phenylenebis（oxy）diacetic acid（C10H10O8） compounds 1 and 2 were obtained via slow evaporation.The compounds were characterized by elemental analysis,IR and single-crystal X-ray diffraction.Compound 1（C10H14O8） crystallizes in the triclinic system,space group P1 with a = 6.3751（6）,b = 8.5311（8）,c = 11.4510（11）A,α = 93.3650（10）,β = 105.3190（10）,γ = 97.2140（10）°,V = 593.15（10） A^3,Z = 2,Mr = 262.21,Dc = 1.468 g/cm^3,F（000） = 276,GOOF = 1.005,° = 0.129 mm^-1,the final R = 0.0361 and w R = 0.0802 for 1854 observed reflections with I 〉 2σ（I）.Compound 2（C30H28N2O12） crystallizes in the triclinic system,space group P1 with a = 9.7416（13）,b = 11.839（2）,c = 12.9828（13） A,α = 74.191（4）,β = 77.953（2）,γ = 74.726（3）°,V = 1374.5（3） A^3,Z = 2,Mr = 608.54,Dc = 1.470 g/cm^3,F（000） = 636,GOOF = 1.061,° = 0.115 mm^-1,the final R = 0.0500 and w R = 0.1221 for 3966 observed reflections with I 〉 2σ（I）.Both compounds 1 and 2 exhibit 3D supramolecular structures under hydrogen bonding interactions.The results of preliminary antibacterial activity show that the title compounds display moderate antibacterial activities against the tested gram positive bacteria（S.aureus,C.albicans and B.subtilis） and gram negative bacteria（E.coli and P.aeruginosa）.

Inhibitory Effects of Chlorpheniramine and Astemizolum on Contraction of Isolated Rat and Rabbit Uteri Induced by Oxytocin an

The contraction of isolated rat and rabbit uteri induced by oxytocin and PGF2α was markedly inhibited by chlorpheniramine (Chl) and astemizolum (Ast) , both of which also decreased the resting tension of uteri, and their spontaneous contraction. The inhibitory effects of both drugs were dose-dependent. At high concentrations , Chl 7. 4 × 10-4 mol/L and Ast 10-4 mol/L could counteract the contraction of the uteri induced by Oxy and PGF2α, and their spontaneous contraction as well. They decreased the resting tension to the lower level. The mechanism of their non-special relaxed action on uteri could not be completely explained only by their H1-receptor blocking action. Whether they act by blocking calcium channel or by inhibiting calmodulin (CaM) remains to be further explored.

Synthesis and Crystal Structure of N-phenyl-N-[(o-nitrophenylacetyl)oxy]benzamide

The compound N-phenyl-N-[（o-nitrophenylacetyl）oxy]benzamide （C21HI6N2Os, Mr = 376） has been synthesized by the reaction of N-hydroxy-N-phenylbenzamide with 2-（2-nitro- phenyl）acetyl chloride in dichlorom-ethane and its structure Was characterized by 1H NMR, 13C NMR, IR, H RMS（ESI） and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic, space group C2/c with a = 32.30（2）, b = 8.400（5）, c = 15.099（9） A, fl = 114.256（10）°, V = 3735（4） A3, Z = 8, D, = 1.339 g/cm3, F（000） = 1568, p = 0.097 mm-1, the final R = 0.0506 and wR = 0.1176 for 2318 observed reflections （1 〉 2a（/））. The title molecule contains three branched chains with its center placed at the midpoint of N. The phenyl ring （C（1）＇-C（6）） makes a dihedral angle of 70.3（1）° with the phenyl ring （C（10）-C（15）） of benzoyl group, and 14.3（1）° with the phenyl ring （C（16） - C（21））, Hydrogen bonds C（5）-H（5）...O（1） and C（12）-H（12）...O（3） together with it-Jr stacking interactions contribute to the stability of the structure.

THEORETICAL STUDIES ON THE INVERSION REACTLON OF BYL(?)OXY LAMINE H_2NOH

The inversion reaction of hydroxy lamine was investigated by using the ab initiointrinsic reaction coordinate(IRC)method with 4-31G basis set.Our results indicate that the ∠H_1NO changes arastically in the vicinity of the transition state while the other bo-nd angles and bond lengths change little throughout the reaction process.

Syntheses and Herbicidal Activity of New Pyrimidinyl（triazinyl）oxy Substituted Carboxylic Derivatives

New compounds were synthesized,which belong to 3 types of pyrimidinyl(triazinyl)oxy substituted carboxylic derivatives respectively.In bioassay,the effects of the structural factors on the herbicidal activity were investigated,in which the stereochemistry has a strong influence on the activity.

《小问题》2021-2解答

问题:如图1所示,一船(可以看作一点)在北半球以匀速度v并始终与经线成θ角的方向向南偏东航行,已知地球半径为R,船所在地的纬度为φ。试用刚体定点运动知识求船相对于地球的加速度。解答:如图2所示,建立坐标系Oxyz,O为地心,Oxy为赤道平面,Oyz为船所在子午面,Ox轴垂直于子午面.

OXY型β-内酰胺酶研究进展

OXY型β-内酰胺酶是由产酸克雷伯菌产生的染色体β-内酰胺酶，迄今至少发现6种（OXY-1-OXY-6）。OXY酶属于Ambler分类的A类和Bush分类的2be亚群。其特点是优先水解青霉素类，表现为对氨基和羧基青霉素的耐药，也可水解一些广谱头孢菌素和氨曲南，其活性可被克拉维酸所抑制；OXY酶具有多样性，一种酶可表现为多种不同的等电点；bla基因的启动子区和Ω环的点突变可能改变它的水解底物谱。

OXY吸油粉末爽肤水 无油激爽，潮人必备

分手不爽!考试不爽!加班不爽。什么都不爽．至少面子要爽！有油光？不爽？OXY吸油粉末爽肤水，带给你前所未有的激爽感觉。

Unraveling the role of NiSnPH@OOH/CC perovskite hydroxide for efficient electrocatalytic oxidation of methanol to formate

The sluggish kinetics of oxygen evolution reaction(OER)is the key tailback for hydrogen production from the water electrolysis.Masking OER with thermodynamically auspicious methanol oxidation reaction(MOR)can significantly boost the H_(2) and value-added products production.However,it is currently challenging to achieve a synergistic manipulation of product selectivity and performance for MOR electrocatalyst.Herein,we report NiSnPH@OOH/CC(CC=carbon cloth)perovskite hydroxide nanosphere as an efficient MOR electrocatalyst with high activity,stability,and selectivity towards methanol oxidation to formate.A surface amorphous layer of defect rich NiOOH was generated in operando by selective Sn leaching with stable perovskite hydroxide bulk structure,which mitigates the oxidative power and optimizes the local coordination environment of the active NiOOH sites.In situ Raman combined with electrochemical studies further confirm the key active species,NiOOH,generated in operando enhance the MOR and blocking the over oxidation of methanol to CO_(2).As a result,NiSnPH@OOH/CC effectively masks the OER and attains>99%selectivity with 100%Faradic efficiency for methanol-to-formate.The results of this study show the advances of NiSnPH@OOH/CC as an efficient electrocatalyst for MOR and also suggest its potential applications for various small organic molecules oxidation.

Regulate electric double layer for one-step synthesize and modulate the morphology of(oxy)hydroxides

FeOOH have received considerable attention due to their natural abundance and cost-effectiveness.Despite the significant progress achieved,the one-step synthesis of integrated FeOOH is still a major challenge.Meanwhile,the current research on FeOOH catalyst still suffers from the unclear mechanism of controlling morphology.Here,density functional theory(DFT)calculations and X-ray photoelectron spectroscopy(XPS)demonstrated the strong electron-capturing and hydrogen absorption ability of Co in FeOOH,which further promotes the formation and stabilization of FeOOH.We used a one-step electrodeposition method to synthesize Co introduced FeOOH integrated electrocatalyst and propose to introduce ions with different valence states to regulate the morphology of FeOOH by precise modulation of electric double layer(EDL)composition and thickness.The prepared Co-FeOOH-K^(+)has a larger electrochemically active surface area(ECSA)(325 cm^(2))and turnover frequency(TOF)value(0.75 s^(-1)).In the electrochemical experiments of an alkaline anion exchange membrane electrolyzer,Co-FeOOH-K^(+)shows better oxygen evolution performance than commercial RuO_(2) under industrial production conditions and has good industrial application prospects.