The Aerobic Biodegradability of Mono-fluorophenols by the Activated Sludge

By measuring the respiratory oxygen consumption, a study on the aerobic biodegradability of 2-fluorophenol, 3- fluorophenol and 4-fluorophenol was conducted using activated sludge acclimated by themselves respectively. The experimental results showed that bio-oxidation ratios of 2- fluorophenol, 3- fluorophenol and 4- fluorophenol were 25.30%, 35.28% and 36.60% respectively, and the constmdng rate constants were 0.009 3, 0.013 3 and 0.014 5 L/ gSS. h respect/vdy. The aerobic biodegradability of the mono-fluorophenols decreased in the order of 4- fluorop- henol〉3 - fluorophenol 〉2 - fluorophenol, resulting mainly from the different octanol/water partition coefficient and the different steric parameter of the fluorophenols which can affect the penetration of fluorophenol into cell membrane.     

PBs/PET共混体系的制备与表征

以丁二酸、丁二醇为原料,通过直接缩聚反应合成了高分子量聚丁二酸丁二醇酯。并将聚丁二酸丁二醇酯 (PBS)同聚对苯二甲酸乙二醇酯 (PET)在不同温度下熔融共混。测定了不同组分共混物的熔点和水降解性。聚合物熔融峰随着共混时间的增加渐渐的下移。这说明PBS和PET热降解和酯交换反应随着共混温度的增加而同时发生。共混物的降解性与芳香组分的含量和链段长度都有关。     

Reductive Degradation Behavior of Bioreducible Poly(disulfide amine) for Enhancing SiRNA Efficiency

Bioreducible cationic polymer poly(CBA‐DAH) containing repeated disulfide linkages on the polymer backbone was synthesized through Michael‐type polyadditions of CBA to DAH monomers. Poly(CBA‐DAH) could spontaneously form nanoscale polyelectrolyte complexes through electrostatic interactions with siRNA in an aqueous phase. These nanoparticles were rapidly degraded under the reductive cytoplasmic environment with subsequently releasing the siRNA cargo into the cytoplasm where RNAi takes place, as a result of the breakdown of disulfide bonds in the polymers. The reductive degradation behavior of the poly(CBA‐DAH)/siRNA polyplexes is more likely to increase RNAi activity with enhancing the cytoplasmic localization of siRNA molecules. Poly(CBA‐DAH) may have great potential as a gene carrier especially for therapeutic applications of siRNAs owing to the reductive degradation characteristics.

     

微电解法处理染化废水的试验研究

染化废水污染物种类多,毒性大、化学需氧量,ρ(CODcr)高,且大部分是生物难降解的污染物质,严重污染环境;利用铁炭在水中发生的微电解过程可有效去除染料生产废水的色度和化学需氧量ρ(CODcr),同时提高污水的后续可生化性.试验结果表明,微电解处理效果受填料组成、pH值、停留时间和混凝曝气等因素的影响;废水经过微电解处理后,ρ(CODcr)和色度分别从2 000 mg/L和2 048下降为860 mg/L和256,去除率可高达56％和75％;采用微电解-混凝法出水与采用单纯的石灰乳中和混凝沉淀法出水相比,ρ(CODcr)降低22.5％,可生化性提高18％.     

非均相CWO法对难降解印染废水色度的去除

通过单因素实验和正交实验,研究了采用Cu-Fe-La/FSC催化剂的CWO法处理印染废水影响因素,以及优化操作条件下的水样可生化性.结果表明:水样脱色率随催化剂用量、反应温度、反应总压的增加和反应时间的延长而提高,随进水浓度的升高而降低;各因素对水样处理的影响为:反应温度>反应时间>催化剂用量>反应总压>进水浓度;CW...     

交联对CO_2共聚物为基的聚氨酯降解性能的影响

讨论了CO2 共聚物为基的聚氨酯 -聚碳酸亚乙酯聚氨酯 (PEC-PU)交联方式、交联程度对其生物降解性能的影响。实验结果显示 ,交联程度越大 ,降解程度有所降低 ,但一定交联程度的交联型PEC -PU仍然具有良好的生物降解性能。     

Synthesis of hyperbranched polymers from vegetable oil based monomers via ozonolysis pathway

In this work, a variety of hyperbranched polymers (HBPs), such as hyperbranched polycarbonates, polyesters, polyurethanes and polyacetals, was successfully synthesized from castor oil and soybean oil based monomers via a A₂ + B₃ polycondensation. First, B₃ monomer triols (TriOL), trialdehydes (TriAD), and tricarboxylic acids (TriAC) were obtained by ozonolysis of castor oil and soybean oil with following reductive or oxidative treatment. Their structures were characterized by ¹H NMR and ATR‐FTIR spectroscopy as well as electrospray ionization‐Time of Flight‐mass spectrometry. These trifunctional B₃ monomers were applied in the preparation of HBPs. The resulting HBPs had number averaged molar mass (M_n) up to 9400 g/mol and weight averaged molar mass (M_w) up to 40,000 g/mol. Through adjusting the initial molar ratio of A₂ to B₃ monomers, hydroxyl terminated (from TriOL monomers) or carboxylic acid (from TriAC monomers) terminated HBPs could be obtained. All the HBPs were characterized by ¹H NMR, size exclusion chromatography, and DSC. These HBPs are potential candidates for the synthesis of cross‐linked polymeric materials or in biomedical applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2104–2114     

Studies on synthesis and characterization of waterborne polyurethane from epigallocatechin-3-gallate

A novel waterborne polyurethane (PU), based on (-)-epigallocatechin-3-gallate (EGCG) that contains phenolic hydroxyl group, was successfully synthesized and characterized. The structural study of PU based on EGCG through FT-IR confirmed the incorporation of EGCG into the chain of PU. The results of X-ray diffraction (XRD) showed that the introduction of EGCG changed the crystallization behavior of the pure waterborne PU. Thermogravimetric analysis (TGA) results indicated that the PU samples exhibited improved thermal decomposition temperature. The degree of phase segregation of modified PU was confirmed by Scanning electron microscope (SEM) analysis. The physical and biodegradable properties of modified PU indicated a comprehensive performance.     

超声预处理强化印染废水的生物降解性

文章以合肥某纺织厂的实际印染废水为处理对象,将超声波技术作为生化处理的预处理步骤,提高废水的可生化性,与混凝、厌氧生化处理单元组合,优化出一套印染废水的处理工艺.实验结果表明, CODCr质量浓度为1 000～1 500 mg/L的实际印染废水被稀释2倍,超声1 h的反应条件下,废水的CODB/COD值提高了19.7%,且经过组合工艺混凝沉淀-超声-SBR-混凝沉淀处理,出水水质的CODCr去除率达96%以上.     

可吸收抗菌胆道支架的制备及其生物相容性研究

胆道梗阻是临床上高发病率和高死亡率的疾病之一, 而植入可吸收支架以替代或扩张梗阻病灶是理想的治疗方法之一. 以聚(L-丙交酯-co-ε-己内酯)(Poly (L-lactide-co-ε-caprolactone), PLCL) (丙交酯与己内酯的质量比为8020)和聚L-丙交酯(Poly (L-lactide), PLLA)为基质制备了管状支架, 然后以聚六亚甲基胍盐酸盐(Polyhexamethylene Guanidine Hydrochloride, PHMG)涂覆于支架表面制备抗菌涂层, 研究该支架的理化性质、抗菌活性以及在动物体内的生物相容性和十二指肠的通畅性. 结果表明 PLCLPLLA=5050(P50-50)材料的力学性能在所有配比材料中最好. 经PHMG包覆后的PP50-50皮下植入时, 具有良好的抗菌活性和体内良好的生物相容性. 用PP50-50膜制成的支架在28d内在小鼠十二指肠内具有良好的通畅性和支撑性. 组织学和免疫荧光染色显示, 炎症反应发生在早期, 随后消退. 这些结果表明, PP50-50支架可能是治疗胆道狭窄的一种良好选择.