A comparative study for petroleum removal capacities of the bacterial consortia entrapped in sodium alginate,sodium alginate/poly(vinyl alcohol),and bushnell haas agar

The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies.

POLYMERIZATION OF γ-STEARYL-α,l-GLUTAMATE N-CARBOXYANHYDRIDE USING RARE EARTH COORDINATION CATALYSTS

A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.

Effect of Sodium Alginate Concentration on Membrane Strength and Permeating Property of Poly-l-arginine Group Microcapsule

A novel poly-/-arginine microcapsule was prepared due to its nutritional function and pharmacological efficacy. A high-voltage electrostatic droplet generator was used to make uniform microcapsules. The results show that the membrane strength and permeating property are both remarkably affected with the changes of sodium alginate concentration. With the sodium alginate concentration increasing, gel beads sizes increase from 233μm to 350μm, release ratio is also higher at the same time, but the membrane strength decreases.

Aggregation of Sodium Dodecyl Sulfonate in Poly-ethylene Glycol Aqueous Solutions Studied by Two-dimensional Nuclear Overhauser Enhancement Spectroscopy

Two-dimensional nuclear overhauser enhancement (2D NOESY)measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the. Normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.

POLYMERIZATION OF ETHYLENE METHYL PHOSPHATE IN THE PRESENCE OF SODIUM POLY(ETHYLENE GLYCOL)ATE

Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. The effects of the factors such as solvent, amount of the initiator and reaction time were investigated. The copolymers were characterized by IR, H-1-NMR, H-1{P-31}-NMR, C-13-NMR, P-31{H-1}-NMR, and DSC. High molecular weight of the copolymer and high yield of the polymerization were achieved within 3 min at 25 degrees C. The polymerization process was studied by P-31{H-1}-NMR and transesterification was found during longer polymerization time.

INTERACTION OF POLY(SODIUM SULFODECYL METHACRYLATE)WITH CETYLTRIMETHYL AMMONIUM BROMIDE IN AQUEOUS SOLUTION

The interaction of poly(sodium sulfodecyl methacrylate) (PSSM) with cetyltrimethyl ammonium bromide (CTAB)was studied. It was found that the precipitate formed from PSSM and CTAB will be dissolved by excessive CTAB, resultingin the appearance of two maxima of the solution viscosity at the molar ratio (CTAB/-SO_3^-) of≈ 0.68 and≈1.30,respectively. The first one is related closely to the aggregation of polymer chains via CTAB molecules and the second oneshould be ascribed to the formation of the mixed micelles comprising surfactant and the polymer's hydrophobic chains. Theeffect of NaCl on the viscosity, the transmittance of the aqueous solution and the solubility of oil-soluble dye (dimethyl yellow) in the mixed system were also investigated.

Combretastatin A4/poly(L-glutamic acid)-graft-PEG conjugates self-assembled to nanoparticles

Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80～120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy.

Study of radiation-induced grafting of acrylic acid-sodium styrene sulfonate onto poly (tetrafluoroethylene-co-hexafluoropropylene) film

Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS), then irradiated by Co γ-rays at 25℃. The effects of reaction 60 time,absorbed dose, dose-rate, inhibitor and monomer concentration on the grafting yield were studied. Grafting yields of both AA and SSS onto FEP, respectively, increase with irradiation dose, but some saturation will appear at high dose and monomer concentration. The grafting yield increases with reaction time and then levels off. The graft- ing of SSS onto FEP is more difficult than the grafting of AA. The analysis of grafted membranes using DSC and FT-IR have been done.

Microanalyses of the hydroxyl-poly-calcium sodium phosphate coatings produced by ion beam assisted deposition

Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3^-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.

Separation Performance of Sodium Alginate/Poly(Vinyl Pyrrolidone)Membranes for Aqueous/Dimethylformamide Mixtures by Vapor Permeation and Vapor Permeation with Temperature Difference Methods

In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and their performance was examined by varying experimental parameters such as feed composition (0 - 100 wt%), operating temperature (30℃ - 50℃) and membrane thickness (30 - 90 micrometer (μm)). Blending NaAlg with PVP, decreased separation factor whereas increased the permeation rate as the permeation temperature was increased in Vapor Permeation (VP) and Vapor Permeation with Temperature Difference (TDVP) methods. In the TDVP method, the separation factors increased and the permeation rates decreased as the temperature of the membrane surrounding is decreased. The highest separation factor of 60 was obtained in TDVP method for 90 wt% DMF concentration in the feed.

3种不同添加物对凡纳滨对虾生长、非特异免疫和抗病力的影响

为评估3种不同添加物对凡纳滨对虾(Litopenaeus vannamei)生长性能、非特异免疫反应及抗病力的影响,在基础饲料中分别添加了丁酸梭菌CBG01(Clostridium butyricum CBG01)活菌(CB组)、3%聚β-羟基丁酸酯(PHB组)和1%丁酸钠(BS组)来投喂对虾,对照组投喂基础饲料,养殖6周后测量对虾生长情况、检测血清非特异免疫指标和肝胰腺免疫相关基因表达水平,进行副溶血弧菌(Vibrio parahaemolyticus)攻毒实验。研究表明,CB组和PHB组对虾末体质量和特定生长率显著高于对照组(P<0.05),CB组最高,BS组与对照组差异不显著(P>0.05)。3个处理组对虾成活率和饲料效率均显著高于对照组(P<0.05)。3个处理组对虾血清中溶菌酶、过氧化物酶、超氧化物歧化酶活性以及总抗氧化能力显著高于对照组(P<0.05),CB组对虾血清中碱性磷酸酶、酸性磷酸酶、酚氧化酶活性显著高于对照组(P<0.05),PHB组对虾血清中碱性磷酸酶、酸性磷酸酶、总一氧化氮合酶活性显著高于对照组(P<0.05),BS组对虾血清中酸性磷酸酶活性显著高于对照组(P<0.05)。与对照组相比,CB组对虾肝胰腺中所有免疫相关基因(SOD、LZM、proPO、LGBP、HSP70、Imd、Toll、Relish、TOR、4E-BP、eIF4E1α、eIF4E2)相对表达量均显著上调(P<0.05),而PHB组的Toll基因以及BS组的Imd、Toll、Relish、eIF4E2基因相对表达量与对照组无显著差异(P>0.05)。副溶血弧菌攻毒实验表明,3个处理组对虾的累积死亡率均显著低于对照组(P<0.05)。研究结果表明,饲料中添加丁酸梭菌、PHB和丁酸钠均可不同程度地提高凡纳滨对虾的生长性能和非特异免疫能力,能够显著提高对虾对副溶血弧菌感染的抵抗力。总体比较,添加丁酸梭菌和PHB的作用效果基本相当,在一定程度上要优于添加丁酸钠。在饲料生产加工过程中,在难以添加丁酸梭菌活菌的情况下,建议适当添加聚β-羟基丁酸酯来替代丁酸梭菌。

聚苯乙烯磺酸钠与季鏻盐表面活性剂复合物的结构调控及其抗菌性能

发展非抗生素抗菌策略在减少医疗器械相关的细菌感染并降低对抗生素的过度依赖方面具有重大意义。对医疗器械表面进行功能化,赋予其抗菌性能是非抗生素抗菌所采用的常用方式。聚电解质-表面活性剂复合物的醇溶、水不溶的特点使其在构建抗菌涂层方面具有操作简单、不受器械结构限制的优点,有望应用于各种医疗器械的表面功能化。本文通过构建不同烷基链长季鏻盐表面活性剂与聚苯乙烯磺酸钠聚阴离子复合物,系统研究了复合物在水溶液中的组装行为以及所制备复合物涂层的抗菌性能与表面活性剂组分疏水碳链长度之间的内在关联。通过浊度、等温滴定量热法等测试手段对聚苯乙烯磺酸钠与3种三丁基烷基季鏻盐表面活性剂在水中的组装过程进行了分析,结果表明增加表面活性剂烷基链长将促进聚电解质-表面活性剂复合物形成。通过在常用医疗器械材料表面构建复合物涂层,对比了3种复合物对两种模型菌种的抗菌性能。对于以金黄色葡萄球菌为代表的革兰氏阳性菌,所制备的3种复合物涂层的杀菌率分别为42.9%、99.97%和99.99%,随着表面活性剂烷基链越长而提高;对于大肠杆菌为代表的革兰氏阴性菌,随着表面活性剂烷基链长度增加,单独季鏻盐表面活性剂的抗菌性能增强,而其对应复合物涂层的抗菌性能有所下降,杀菌率分别为99.3%、92.3%和64.8%。以上结果表明,通过优化结构,此类聚电解质-表面活性剂复合物涂层有望用于减少医疗器械相关感染。

Effect of toll-like receptor 3 agonist poly I:C on intestinal mucosa and epithelial barrier function in mouse models of acute colitis

AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium(DSS)-induced acute colitis.METHODS Thirty C57BL/6 mice were given either regular drinking water(control group) or 2%(w/v) DSS drinking water(model and poly I:C groups) ad libitum for 7 d. Poly I:C was administrated subcutaneously (20 μg/mouse) 2 h prior to DSS induction in mice of the poly I:C group. Severity of colitis was evaluated by disease activity index, body weight, colon length, histology and myeloperoxidase (MPO) activity, as well as the production of proinflammatory cytokines, including tumor necrosis factor-α(TNF-α), interleukin 17(IL-17) and interferon-γ (IFN-γ). Intestinal permeability was analyzed by the fluorescein isothiocyanate labeleddextran (FITC-D) method. Ultrastructural features of the colon tissue were observed under electron microscopy. Expressions of tight junction(TJ) proteins, including zo-1, occludin and claudin-1, were measured by immunohistochemistry/immunofluorescence, Western blot and real-time quantitative polymerase chain reaction(RT-qPCR).RESULTS DSS caused significant damage to the colon tissue in the model group. Administration of poly I:C dramatically protected against DSS-induced colitis, as demonstrated by less body weight loss, lower disease activity index score, longer colon length, colonic MPO activity, and improved macroscopic and histological scores. It also ameliorated DSS-induced ultrastructural changes of the colon epithelium, as observed under scanning electron microscopy, as well as FITC-D permeability. The m RNA and protein expressions of TJ protein, zo-1, occludin and claudin-1 were also found to be significantly enhanced in the poly I:C group, as determined by immunohistochemistry/immunofluorescence, Western blot and RT-q PCR. By contrast, poly I:C pretreatment markedly reversed the DSS-induced up-regulated expressions of the inflammatory cytokines TNF-α, IL-17 and IFN-γ.CONCLUSION Our study suggested that poly I:C may protect against DSS-induced colitis through maintaining integrity of the epithelial barrier and regulating innate immune responses, which may shed light on the therapeutic potential of poly I:C in human colitis.

Development of Polycaprolactone/Poly(Vinyl Alcohol)/Clay Microparticles by Spray Drying

In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25®by using the spray drying technique. The systems obtained were characterized by Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic Laser Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The NMR 13C and FTIR techniques showed that both polymers were present in the microparticles and the DSC analysis revealed a small variation in the glass transition temperature of the PCL. The XRD and SEM analyses showed that the microparticles produced were amorphous and had a concave morphology. The NT-25 nanoload reduced the microparticles’ size due to the multiple interactions formed in the hybrid nanocomposite material. Therefore, it was possible to develop microparticles by using biodegradable and biocompatible polymers, with different polarities, allowing the incorporation of hydrophilic and hydrophobic materials and enabling the inclusion of otherwise incompatible materials in the same system.

聚电解质盐三聚磷酸钠对聚乙烯醇凝胶的Hofmeister效应研究

聚乙烯醇(PVA)物理微晶水凝胶由于化学稳定性好、无毒、生物相容性好等特点,近年来成为物理微晶凝胶研究的模板聚合物。但其力学性能较差,如何提高凝胶的力学性能,拓展其应用范围一直是水凝胶领域的研究难点和热点。Hofmeister盐析效应是提升凝胶力学性能一种高效、绿色的制备手段,但之前的研究多集中在小分子无机盐对凝胶性能的影响,对聚电解质盐的盐析效应鲜见报道。本文研究了三聚磷酸钠(STPP)聚电解质对PVA凝胶性能的影响,系统比较了其与氯化钠及氢氧化钠处理的PVA凝胶;重点从微观形态和结晶结构两方面研究了聚电解质盐与小分子盐引起PVA凝胶的微观结构差异,并分析了结构与性能间的响应关系。聚电解质STPP处理的PVA凝胶薄膜应力达到了23 MPa,应变高达1 100%,断裂韧性(110 MJ/cm^(3)),比纯水凝胶提升55倍之多,并兼具良好的阻燃性能。

聚丙烯酸钠对聚丁二酸丁二醇酯水解性能的影响

采用熔融共混法制备了聚丁二酸丁二醇酯/聚丙烯酸钠(PBS/PAAS)共混物,探究PAAS对PBS水解性能的影响。通过吸水率和失重率分析了共混物的水解性能,利用拉力试验机、差示扫描量热、扫描电镜和X射线衍射仪等对共混物的力学性能及水解前后结晶性能、微观形貌和结晶结构进行表征。结果表明,随PAAS用量的增大,共混物基体孔洞增多,水解性能有较大提升。当PAAS用量为100份时,共混物的吸水率最高为110.1%,水解失重率为44.6%;加入PAAS后,共混物的拉伸强度、屈服强度和断裂伸长率降低,弹性模量升高。PAAS可以提高共混物的结晶温度,但对熔融温度影响不大,随水解时间的延长,共混物的熔融温度没有发生变化,但PBS组分的熔融焓变化明显。同时,水解过程中共混物中PBS的晶型没有变化。

脂肪醇聚氧乙烯醚的原料指标对AES中二噁烷含量的影响

为研究脂肪醇聚氧乙烯醚原料(简称AEO)对脂肪醇聚氧乙烯醚硫酸钠(AES)中二噁烷的影响,在嘉兴赞宇工厂的膜式磺化器装置上,考察了AEO中水分含量、PEG含量、环氧乙烷含量对AES中二噁烷含量的影响。结果表明:随着AEO中水分、PEG、环氧乙烷含量的增加,使AES中二噁烷增加,特别是环氧乙烷的影响最为显著,并且环氧乙烷的增加与二噁烷含量的增加呈非线性关系。文中从反应机理上进行了推导和解释。

Two dimensional MoS_(2) finding its way towards constructing high-performance alkaline recovery membranes

The available alkaline recovery membranes are currently dominated by polymeric materials,but they suffer from a permeation-selectivity trade-off and inferior chemical resistance.Robust two dimensional(2D) lamellar membranes with sub-nanometer wide channels are promising candidates for discerning OH^(-)and other anions.Here,we report the development of alkaline recycling membranes through stacking MoS_(2) nanosheets.Benefiting from the ordered and narrow 2D channels,MoS_(2) membranes show excellent alkaline recovery performances.The OH^(-)dialysis coefficient (U_(OH)-) and separation factor (S)towards simulated OH^(-) and WO_(4)^(2-) across the 500 nm thick MoS_(2) laminates reach 6.9×10^(-3)m·h^(-1)and 34.3 respectively.Furthermore,the chemical environments of MoS_(2) laminates were modulated by intercalating ionic poly(sodium 4-styrene sulfonate)(PSS@MoS_(2)).The U_(OH)-and S values of PSS@MoS_(2) membrane further improve to 11.7×10^(-3)m·h^(-1)and 49.8 respectively.Besides,both MoS_(2) and PSS@MoS_(2) membranes exhibit promising stability.

聚乙烯醇/淀粉复合膜的制备及其对鲜花保鲜效果研究

以木薯淀粉和聚乙烯醇作为基本成膜物质,添加表面活性剂十二烷基磺酸钠,通过流延成膜法制备聚乙烯醇/淀粉复合膜。在单因素试验基础上,研究木薯淀粉、聚乙烯醇、表面活性剂十二烷基磺酸钠用量,成型加工温度和成型加工时间对聚乙烯醇/淀粉复合膜力学性能的影响,并通过正交试验对木薯淀粉、十二烷基磺酸钠用量和成型加工时间3个因素进行优化,确定聚乙烯醇/淀粉复合膜性能的较优工艺条件。同时,对新制备的复合膜土埋降解和鲜花保鲜性能进行了研究。结果表明:当聚乙烯醇用量为1 g,木薯淀粉用量为0.7 g,十二烷基磺酸钠用量为0.5 g,成型加工温度为80℃,成型加工时间为65 min时,制备的聚乙烯醇/淀粉复合膜力学性能较优,断裂伸长率高达262.58%、拉伸强度24.63 MPa。获得的新复合膜具有可降解性。聚乙烯醇/淀粉复合膜储藏80 h以后无霉菌生长迹象,对鲜花有一定保鲜效果。

工业硫化钠法常压合成线型高分子量聚苯硫醚的研究

以精制工业硫化钠和对二氯苯为原料，采用多组分催化剂，在六甲基磷酰三胺（ＨＭＰＡ）中进行常压溶液缩聚，合成了线型高分子量的聚苯硫醚（ＬＨＰＰＳ）。研究了单体的配比、工业硫化钠的脱水和体系中含水量对聚合反应的影响，探索了聚合反应过程中分子量的增长状况。测定了合成产品的熔融粘度和溶液粘度，应用元素分析、傅里叶变换红外光谱对合成产品进行了分析表征。用ＤＳＣ和ＴＧＡ测定了树脂的熔点Ｔｍ和初始热失重Ｔｄ，通过熔融挤出考察了树脂的加工热稳定性。结果表明，合成的树脂为线型高分子量ＰＰＳ树脂，具有优良的热性能和加工热稳定性。