硫化物微生物电极的研制及应用

１引言 测定硫化物常用对氨基二甲基苯胺分光光度法和碘量法,前者显色条件不易控制、操作繁琐、不适于有色和混浊样品;后者适于含量＞１ｍｇ／Ｌ的样品、试剂用量大、成本高。微生物电极法设备简单、操作简便、试剂用量少、成本低,我们以氧化硫硫杆菌为分子识别元件,研制了一种硫化物微生物电极,实验证明,其性能优于Ｋｕｒｏｓａｗｓ　Ｈ等研制的硫化物微生物传感器,用其测定样品的结果与分光光度法一致。２实验部分２．１仪器及试剂ＳＪＧ－２０３型溶解氧分析仪和极谱型氧电极（上海雷磁仪器厂）;恒温水浴;Ｃ１３－μＡ型电流计…     

气相色谱分析虫霉菌液体中的脂肪酸

研究了气相色谱测定虫霉菌液体中脂肪酸的分析方法。样品经石油醚－苯混合溶剂提取，用KOH－CH3OH溶液进行甲酯比，用GC－FTD 10％DEGS为分离柱。测定脂肪酸的组成。共鉴定出C16：0软脂酸，C18：1油酸，C18：2亚油酸等为主的八种脂肪酸。     

表面活性剂PAA对羟基磷灰石微粒分散性的调控及机理研究

羟基磷灰石(hydroxyapatite,HAP)因其具有优良的生物相容性和生物活性而被广泛应用于临床。但由于制备过程中不可避免的团聚,严重影响其性能。本文首次借助阴离子表面活性剂聚丙烯酸(PAA),通过控制PAA的含量成功制备具有不同颗粒尺寸的HAP粉末样品,进而调控其分散性;同时借助多种表征技术包括扫描电子显微镜(SEM),X射线衍射(XRD)及粒径分析仪等等,获取HAP样品微观形貌及粒径尺寸,深入探究表面活性剂PAA对HAP微粒分散性的影响机制。     

不同有机分子改性羟基磷灰石用于甲醛催化氧化

分别采用十六烷基三甲基溴化铵(CTAB)、十二烷基硫酸钠(SDS)及柠檬酸钠(SC)对羟基磷灰石(HAP)进行了有机改性.柠檬酸钠改性的羟基磷灰石对甲醛催化氧化表现出最好的催化活性,在240℃实现了甲醛完全转化.通过X射线衍射、红外光谱、N2吸附-脱附、扫描电镜和热重/差重等手段对HAP结构进行了表征.结果表明,SC改性使得HAP比表面积和孔体积增加,孔径减小,更有利于吸附及传质,从而提高了其活性.此外,SC改性的HAP中羟基含量更多,更有利于甲醛与羟基之间发生相互作用,这是该样品活性提高的另一个原因.     

RE(C7H5O3)2(C9H6NO)配合物抗真菌作用的热动力学研究

应用微量热法研究了配合物RE（CTH5O3）2（C9H6NO）（RE代表La，Sm和Nd）对真菌的抗菌作用。在TAM Air热导式等温微量量热仪上，分别测定了桔青霉菌和黑曲霉菌在不同浓度不同稀土配合物及空白条件下生长代谢热谱曲线，并计算得到了真菌在不同条件下的生长代谢速率常数k和传代时间G等热动力学参数。实验表明：3种稀土水杨酸8-羟基喹啉三元配合物对桔青霉菌和黑曲霉菌均有抑制作用，其抑制效果依次为：Sm（Hsal）2（hq）〉La（Hsal）2（hq）〉Nd（Hsal）2（hq）。     

羟基磷灰石/丝素蛋白复合纤维的制备及其矿化研究

在以静电纺丝法制备羟基磷灰石(HAP)/丝素蛋白(SF)复合纤维的前提下, 采用同轴共纺法获得了以HAP为“芯”、SF为“皮”的双组分电纺纤维(电纺膜), 并通过扫描和透射电镜、红外光谱以及X射线衍射等手段对电纺纤维进行了表征. 结果表明, HAP均存在于上述两种方法制备的纳米纤维中, 但同轴共纺法不仅可以避免HAP/SF共混电纺时pH值对丝素蛋白结构的影响, 并且能大大提高电纺膜中HAP的含量. 同时, 我们还分别以SF纤维、HAP/SF复合纤维和HAP/SF“皮-芯”纤维作为有机基质, 对羟基磷灰石在其上的矿化过程进行了探索, 结果表明含较多羟基磷灰石的HAP/SF“皮-芯”纤维更有利于矿化的进行.     

微生物电极法测定啤酒中乙醇含量

用自制的乙醇微生物电极建立了一种测定啤酒中乙醇含量的新方法。该法具有良好的精密度和准确度，其测定结果与比重瓶法和气相色谱法相一致，回收率为９７．３％－１０４．９％。该电极线性范围为０．３－１２．０ｍｇ／Ｌ，６０天测定６００余次，其灵敏度基本稳定。测试的最适酸度范围为ｐＨ６．４－７．３，温度为３２－３４℃，测定一个样品需５－８ｍｉｎ。     

2’-脱氧腺苷-5’-磷酸与羟基自由基反应所形成的自由基

运用可靠的B3LYP/DZP++方法研究了2'-脱氧腺苷-5'-单磷酸(dAMP)与羟基自由基(HO·)的反应中所产生的20余种自由基. 结果表明, 反应的初始产物包括HO·加成到dAMP碱基C8、C4位上所形成的羟基加合物自由基, 以及dAMP碱基环上氨基的脱氢自由基. 而且,反应最初形成的C4位羟基加合物自由基具有脱水产生dAMP碱基环上氨基脱氢自由基的热力学趋势, 脱水形成的两种氨基脱氢自由基都是强氧化剂.尽管HO·加成到dAMP碱基C2位上所形成的加成产物比C4位的加成产物更稳定, 但dAMP与HO·的氧原子间较强的静电排斥作用却使得HO·难以靠近C2原子, 导致C2位的羟基加成产物难以形成. 上述结论不但与有关实验结果一致, 而且还对一些实验现象作出了合理的解释.     

镉污染对红壤微生物生态特性的影响

在预培红壤中加入不同浓度和固定浓度的Cd，分别在25℃培养14d和30d，前者测定14d后土壤微生物生物量C（Cmic)及土壤微生物对碳素利用状况，后者连续监测土壤微生物基础呼吸强弱，结果表明，Cd对土壤中微生物生物量的毒害作用随着Cd浓度的增加而增强，土壤Cmac随Cd浓度的的增加而降低。Cd污染导致碳源测试盘平均吸光值下降。说明土壤微生物对碳素利用能力下降，同时典型变量分析表明Cd污染导致土壤微生物群落结构发生变化。Cd污染使土壤微生物基础呼吸作用在污染早期相对下降。之后逐渐恢复。但代谢熵明显随着Cd污染而增加。     

毛细管电泳对微生物代谢中硫酸根和硫代硫酸根的分离与测定

建立了微生物代谢中硫酸根和硫代硫酸根的毛细管电泳分析方法．在选定实验条件下，各种阴离子（Ｓ２Ｏ２－３、ＳＯ２－４、ＣＩ－、ＮＯ－３、ＰＯ３－４）在４ ｍｉｎ内达到完全分离，其中 Ｓ２Ｏ２－３和ＳＯ２－４迁移时间的相对标准偏差小于１％，峰面积的相对标准偏差小于５％．测定了４种菌株分别在两种培养基中的Ｓ２Ｏ２－３和ＳＯ２－４浓度随培养时间的变化．结果表明，其中一菌株在ＳＫ基中对Ｓ２Ｏ２－３有明显的氧化作用．     

煤中腐植酸与尿素相互作用机理的研究

采用化学法和波谱分析法对泥炭、褐煤、风化煤腐植酸（ＨＡ）与尿素的相互作用机理进行了研究。结果表明,ＨＡ与尿素之间发生了极其复杂的反应,包括离子化、络合配位、亲核加成、自由基反应及氢键缔合等,形成不同的化学键。羧基对反应深度的影响最大;含官能团（特别是羧基）最多的风化煤ＨＡ反应性最高。本项研究为有机长效尿素的研制提供了理论依据     

杂多酸在膨润土上的固载化：Ⅰ.表面酸性和吸附机理的研究

本文研究了四种具有Ｋｅｇｇｉｎ结构的杂多酸在膨润土及其酸处理样品上的吸附，利用Ｈａｍｍｅｔｔ指示剂法和丁胺滴定法测定了膨润土吸附ＰＷ１２和ＳｉＷ１２前后表面酸强度和酸度的变化。实验表明：四种杂多酸在不同载体上的吸附，对溶剂是有选择性，在一些有机溶剂中，ＰＷ１２和ＳｉＷ１２的吸附等温线都呈Ｌａｎｇｍｕｉｒ型，而ＰＭｏ１２和ＳｉＭｏ１２的吸附等温线随溶剂的不同呈现不同的形式。膨润土吸附杂多酸后酸强度不     

Synthesis and characterization of hydroxy‐bisphosphonate micrometer‐sized particles by dispersion polymerization of a new styrylbisphosphonate monomer

Bisphosphonates (BPs) are nonhydrolyzable pyrophosphate (P‐O‐P) analogs possessing two phosphonate groups linked to a single carbon (P‐C‐P). The hydroxy‐bisphosphonates (hydroxyBPs) are obtained when the hydroxy group is also linked to this bridging carbon. Their ability to form bidentate or tridentate chelates with calcium ions results in a high affinity to hydroxyapatite (HAP) in dentin, enamel and bones. In this study, we designed and prepared crosslinked poly(styrylbisphosphonate) (PStBP) micrometer‐sized particles by dispersion polymerization of the styrylbisphosphonate (StBP) and ethylene glycol dimethacrylate (EDMA) monomers. The new StBP monomer was synthesized in an efficient one‐pot synthesis using tris(trimethylsilyl)phosphite as the phosphorus source followed by methanolysis. The StBP monomer was successfully isolated and characterized as tri‐sodium salt. Polymerization of the StBP monomer was carried out in two steps: in situ conversion of the tri‐sodium StBP monomer back to its acid form, followed by radical dispersion polymerization in the presence of the crosslinker EDMA monomer. The resulting crosslinked PStBP micrometer‐sized particles retained the unique high affinity of the hydroxy‐bisphosphonate side groups to calcium ions and exhibited good adhesive properties to HAP. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

磷灰石晶体构型及其与生物分子相互作用的计算模拟研究

生物磷灰石是动物和人体骨骼及牙釉质的主要无机矿物成分,磷灰石矿物晶体的组成和结构影响了骨及牙釉质的机械强度和生理功能。羟基磷灰石空间群的确定一直存在争议,其中羟基存在两种不同排列方式,使得其具有六方和单斜两种晶相。另外,磷灰石晶体结构中的类质同象替换,影响了其结构、物理和化学特性。本文综述了计算机模拟方法在原子及分子水平上对磷灰石晶体的空间群确定、磷灰石替代机制、小分子及生物大分子相互作用的研究,对磷灰石晶体化学、界面化学及开发生物材料的深入研究具有一定的科学意义和较强的应用价值。     

风化煤的化学降解

在Ｍｎ－Ｍｏ催化剂存在下用ＨＮＯ３氧化对风化煤进行了化学降解研究。考察一降解条件，氧化产物收率及组成性质，结果表明，与原煤相比，氧解产物中极性功能团大量增加，极性溶剂中抽提率显著提高。     

XANES技术探究酸处理对义马煤中硫形态及其热变迁行为的影响

利用XANES技术研究了酸处理对义马煤的比表面积、体相及表面硫形态分布和热解过程中硫变迁行为的影响。结果表明,由于酸处理过程中部分镶嵌于有机质中的矿物质被脱除导致部分闭合孔打开,煤的比表面积有所增大。HCl-HF和HCl-HF-HNO₃处理脱除了煤中大部分矿物质和无机硫,由于HNO₃的强氧化性,YMN中亚砜和砜硫化物的相对含量均高于YMR和YMD。相比煤样体相,酸处理过程对表面形态硫的分布产生了更为明显的影响。酸处理煤样热解含硫气体释放量减少,但由于大部分碱性矿物质的脱除和煤中易分解形态硫相对含量的增加,含硫气体释放率增加。不同形态硫之间的内部转化使得酸处理煤焦中主要形态硫的分布更为均匀。通过HCl-HF-HNO₃处理可以有效地脱除煤中矿物质及无机硫,并改变煤中形态硫分布,从而为高灰分、富含黄铁矿的高硫煤的利用提供指导。     

Characterization and identification of the Detroit River mystery oil spill (2002)

In this paper, a case study of the Detroit River mystery oil spill (2002) is presented that demonstrates the utility of detailed and integrated oil fingerprinting in investigating unknown or suspected oil spills. The detailed diagnostic oil fingerprinting techniques include determination of hydrocarbon groups and semi-quantitative product screening, analysis of oil-characteristic biomarkers and the extended suite of parent and alkylated polycyclic aromatic hydrocarbons (PAHs), and quantitative determination of a variety of diagnostic ratios of "source-specific marker" compounds. The detailed chemical fingerprinting data and results highlight the followings: (1) The spill samples were largely composed of used lube oil mixed with smaller portion of diesel fuel. (2) The diesel in the samples had been weathered and degraded. (3) Sample 3 collected from N. Boblo Island on 14 April was more weathered (most probably caused by more evaporation and water-washing) than samples 1 and 2. (4) All fingerprinting results clearly demonstrated oils in three samples were the same, and they came from the same source. (5) Most PAH compounds were from the diesel portion in the spill samples, while the biomarker compounds were largely from the lube oil. (6) Input of pyrogenic PAHs to the spill samples was clearly demonstrated. The pyrogenic PAHs were most probably produced from combustion and motor lubrication processes, and the lube oil in these spill samples was waste lube oil.     

Molecular simulation of water behaviors on crystal faces of hydroxyapatite

The water behavior on (001) and (100) crystal faces of hydroxyapatite (HAP) were studied using molecular dynamics (MD) simulations. The study showed that the water molecules between the HAP faces were under conditions of strong electrical field and high pressure, and hence formed 2–3 well-organized water layers on the crystal surfaces. These structured water layers had ice-like features. Compared with the crystallographic [100] direction of HAP, the polarity along the [001] direction was stronger, which resulted in more structured water layers on the surface. The interaction of water molecules with the calcium and phosphate sites at the HAP-water interface was also studied. The results indicated the multiple pathways of water adsorption onto the HAP surfaces. This study revealed the formation and the detailed structure of water layers on HAP surfaces and suggested that the interfacial water played an important role in stabilizing the HAP particles in aqueous solutions. Translated from Chinese Journal of Inorganic Chemistry, 2006, 22(8): 1392–1400 (in Chinese)     

The influence of dodecylamine hydrochloride on the dissolution kinetics of heat-treated hydroxyapatite samples

The influence of dodecylamine hydrochloride (DAC) on the dissolution rate behavior of hydroxyapatite (HAP) samples prepared by digestion at 100°C and heated to various temperatures was investigated. The dissolution rates of HAP samples heated to temperatures of 300, 500, 750, 900, 1000, and 1200°C were determined at various levels of DAC in an acetate buffer having a pH of 4.50 and an ionic strength of 0.10. DAC adsorption isotherms for these different HAP samples and the specific surface areas were also determined. The initial dissolution rates (IDR) for all preparations generally decreased with increasing DAC levels with an approximately inverse relationship between IDR and DAC adsorption. For HAP samples heated at 1000°C and higher, the dissolution rates at 3.0 mM DAC were completely inhibited, while for samples heated at 900°C or less, there was a significant residual IDR at 3.0 mM DAC. This residual rate was approximately 20% of the zero DAC rate for all samples treated between 300 and 900°C. These results are in agreement with the concept that HAP prepared by precipitation and digestion at 100°C has two or more kinds of sites for dissolution and that heat treatment at around 1000°C or greater causes the elimination of one or more of these sites.