有机交联膨润土对预处理造纸黑液COD的吸附研究

主要探讨了有机交联膨润土吸附剂（简称TBC）对经酸化絮凝后的造纸黑液进行处理的研究。当pH=4．5，TBC用量为24g·1－1H2O，常温搅拌吸附60min后，其对COD的吸附效率可达61．5％，吸附容量为549．3mgCOD·g－1。     

用D_2EHPA-煤油溶剂萃取分离L-异亮氨酸

本文研究了从发酵液中用D2EHPA－煤油溶剂萃取分离L－异亮氨酸工艺．考察了萃取时pH值、萃取剂浓度和异亮氨酸浓度对于异亮氨酸和缬氨酸的萃取分配比的影响．在计算机上进行回归，得到以下分配模型：当1≤pH≤3．5时lgDIle＝0．09906pH2＋0．8625pH＋2．2696lgCHR－0．09188lg2CIle＋0．1766lgCIle－1．366lgDrmVal＝－0．0293pH2＋0．550pH＋1．2659lgCHR－0．2420lg2CIle＋0．4549lgCIle－1．696用此模型，应用分馏萃取理论，进行逐级计算，求取了萃取工艺的主要参数，并在φ20mm的多级离心萃取器上对上述结果进行了验证．结果表明：当CHR浓度为1．5mol／L，相比V：L：L’＝2：1：2，N’＝3，N＝6时，异亮氨酸的收率达到90％以上，纯度＞99％．实验取得了较为满意的结果．     

铋磷钼蓝光度法测定钛铁矿中的磷

研究了在0．5～1．0mol·L－1的硫酸介质中,利用硝酸钠作还原催化剂,以抗坏血酸将磷钼钻离子还原成磷钼蓝的方法来测定钛铁矿中的磷,其最大吸收峰43λmax=720nm,Σ20=0．6×104L·mol-1·cm－1,磷区在0～50μg·（50mL）-1范围内符合比尔定律。     

依来铬青R光度法测定镀铬液中的铁

系统探讨了在CTMAB存在下，铁（Ⅲ）-依来铬青R（SCR）－CTMAB显色反应的条件：在pH3．5～4．5的HAC－NaAC缓冲介质中，Fe（Ⅲ）－SCR－CIMAB形成1：1：2的络合物，λmax为630nm,630为7．6×104L·mol-1·cm-1，铁含量在0～20μg／25ml，范围内遵守比耳定律，用于镀铬液中杂质铁的测定能获得满意结果。     

培养条件对白腐菌合成脂肪酶的影响

以橄榄油为碳源用白腐菌QB1(Sarcodon asparatus QB1)合成脂肪酶，当碳源浓度为5mg／mL时，在培养基初始pH值为5．5，28℃条件下培养10d，脂肪酶活力为0．65U／mL，菌体干密度为3．05mg／mL，脂肪酶活力在培养基初始pH值为5．0～5．5时最高。当酶反应环境pH值分别为4．0～4．5和6．0～6．5时，脂肪酶相对酶活力分别下降为38％～60％和57％～63％。     

三价铬钝化工艺在金属零件上的应用

1pH的调整 在实验室里，基本上确定了三价铬彩色钝化工艺配方：硝酸铬，20～30g／L；氧化剂，4～5mL／L；pH调整剂，4～6mL／L；pH，1．5～2．0。 根据上述三价铬钝化工艺确定了pH范围，pH低于1．0时钝化膜层发雾，反应较快：pH高于2．5时钝化膜层色泽不均匀。     

碘仿电解合成的机理研究

采用循环伏安法分别研究了铂电极在 0 .1 mol· L- 1 Na2 CO3+0 .0 5mol· L - 1 KI,0 .1 mol· L - 1Na2 CO3+0 .0 5 mol· L- 1 KI+0 .5mol· L- 1 乙醇 ,0 .1 mol· L- 1 Na2 CO3+0 .0 5 mol· L- 1 KI+0 .5 mol· L- 1丙酮溶液中的电化学行为 ,发现含 I- 体系的阳极氧化反应十分复杂 ,除了 I- 被电氧化为 I2 外 ,同时还发生生成 IO3- 等含碘高价化合物的电氧化反应 ,此外电氧化反应过程中还存在多个后续化学反应 ;电化学阴极还原反应则较为简单。中间产物 IO-的作用非常关键 ,IO-攻击甲基酮中 - CH3与 >C=O之间的 C- C键而生成碘仿 ,碘仿电解合成反应中存在着复杂的竟争反应现象。通过循环伏安曲线分析还发现电极过程的控制步骤并非为简单的传质步骤     

732离子交换树脂从胱氨酸母液提取L-精氨酸的研究

实验考察了温度、pH值、氯化铵和氯化钠浓度对 732阳离子交换树脂吸附L -精氨酸的影响 ,并测定了 2 5℃时 732离子交换树脂吸附L -精氨酸的吸附等温线。结果表明 :温度变化对吸附率影响较小 ;pH值增大 ,吸附率下降 ;溶液中氯化铵或氯化钠浓度增大 ,吸附率迅速下降 ,且当氯化铵或氯化钠物质的量浓度达到1.0mol·L-1时 ,L -精氨酸难于被吸附 ;2 5℃时 ,最大饱和吸附量约为 117g·kg-1树脂。根据实验结果开发了从胱氨酸母液提取L -精氨酸的工艺 ,提取率达到 80 %以上。     

碘离子选择电极测定果蔬、药剂中Vc含量

提出用碘离子选择电极测定维生素C与碘在乙醇溶液中发生氧化还原反应时定量释放出游离碘离子溶液中的电位以测定样品中Vc含量的方法。在 0 .1mol·L- 1 KNO3,pH =2 .0～ 6 .0溶液中 ,维生素C的浓度对数值在 10 - 5～ 10 - 1 mol L范围内与电位显示良好的线性关系 ,检测下限为 5×10 - 6 mol L ,回归方程为 ,相关系数为 ,回收率为 92 %～ 10 3% ,相对标准偏差为 2 .3% ,能满足食品、制药及营养研究等行业对Vc的测定。     

羟基铁交联累托石吸附重金属离子Cr6+的研究

研究羟基铁交联累托石的制备及其对Cr^6 的吸附性能。当溶液pH值为3左右，羟基铁交联累托石(以下简称CLR)～的用量为13．2g／LH2O时，常温振荡吸附60min，Cr^6 的去除率可达到98％，残留Cr^6 浓度可降至0．5mg／L以下。     

四株产酸白腐菌应用于碱性造纸黑液生物治理的研究

研究了4株产酸白腐菌在碱性黑液体系中pH值、固体量、酸析与酸溶木质素、COD的变化状况。结果表明碱性对产酸白腐菌具有抑制作用。S4B、S6B及S5B（pH=9）不能适应碱性环境，S1B和S5B（pH＝8）能够适应一定的碱性环境，同时改变体系pH值、木质素和COD。S1B可将环境酸碱度从初始的pH＝8、pH＝9下降到pH=1,即通过产酸与生产降解，去除体系中木质素，COD去除率达73％。说明产酸白腐菌在碱性黑液中可以发挥产酸与降解的双重功能，可应用于黑液的生物处理。     

掺Fe二氧化钛对饮用水深度处理的研究

采用溶胶-凝胶法制备掺Fe的TiO2复合催化剂，选择液固相流化床型光催化反应器，以20W紫外灯为光源，考察了光照时间、pH、通气量、催化剂投加量对饮用水深度处理的影响。结果表明，掺Fe的TiO2复合催化剂对饮用水的处理效果最好，当光照为30min，pH为中性，通气量为1000ml／min，催化剂投加量为2．0g/L时，COD去除率可达到62％以上。     

固定化白腐菌对造纸废水的生物降解研究

就具有较强木质素降解能力的白腐菌对造纸废水的降解效果及条件进行了初步研究.分别采用固定化白腐菌和悬浮态白腐菌在不同接种量下对造纸废水进行降解,对降解过程中的白腐菌生长量、pH、COD、木质素含量等废水降解指标进行测定.结果显示两种不同状态下的白腐菌均能降解造纸废水,但它们的降解程度不同.其中固定化白腐菌降解木质素效果较好,且呈现较明显规律,说明固定化的白腐菌较悬浮态的白腐菌更具有降解造纸废水的潜在能力.     

Synthesis and characterization of biresponsive graft copolymer gels

Graft copolymer gels with different compositions were prepared by the radical polymerization of N-isopropylacrylamide (NIPAAm) and poly(2-vinylpyridine) (P2VP) macromonomers in dioxane with 1 mol% N,N′-methylenebisacrylamide (BIS) as the crosslinking agent. The graft copolymer gels were analyzed at different temperatures and pH values. They demonstrated the typical swelling behavior for poly(N-isopropylacrylamide) (PNIPAAm) gels with changing temperature. In addition to the temperature dependent measurements, the graft copolymer with a high P2VP content showed a pronounced swelling transition with changing pH value. By separating the temperature and the pH sensitive component, it was possible to obtain a gel which could be swelled independently in response to temperature and pH.     

Low density foams produced from sheared ultra-high-molecular-weight polyethylene gels

Low-density foam (0.02–0.09 g/cc) was produced from gels of ultrahigh molecular weight (UHMW) polyethylenes in solvents with melting points above ambient. The hot PE solutions were stirred at high speed to induce extended chain crystalline gels. These gels were subsequently cooled to allow the solvent to solidify and then the solvent was extracted with alcohol or sublimed. This resulted in a tough, low density foam or a collapsed mass depending mainly on the concentration of the polymer. Shrinkage was significant until polymer concentrations reached 4–5%. Foam cell size varied between 5–30 μm, or 25–75 μm depending on the method of preparation. Polarizing microscopy revealed both spherulitic and row-nucleated structures depending on the thermal history followed during the sample preparation. We were also interested in whether or not small particles could be used to influence the nucleation and growth of the solution crystallization process. These particles could be suspended in the gel and stabilized in something like a colloidal necklace as has been proposed recently. We successfully incorporated small (0.5 μm) tungsten particles in UHMWPE gels which remained in the foam on extraction of the solvent. Polyethylene containing carbon black particles produced less successful results. These effects may be related to absorption associated with gelation of UHMWPE.     

Stabilisation of β-glucosidase entrapped in alginate and polyacrylamide gels towards thermal and proteolytic deactivation

β-D -Glucosidase was immobilised by entrapment in two different matrices (calcium alginate and polyacrylamide gels), in order to compare how the immobilisation could stabilise the enzyme towards thermal and proteolytic deactivation. While the enzyme trapped in polyacrylamide gel showed an optimum temperature for activity at 10°C lower than that of the free enzyme, the optimal temperature after immobilisation in alginate beads was not altered (60°C). The immobilisation of enzyme in alginate beads caused a larger increase in the thermal stability than the entrapment in polyacrylamide gels. The stabilisation factors obtained as 55, 60 and 65°C for β-glucosidase immobilised in alginate and polyacrylamide gels were 2·03, 3·06, 2·19 and 2·04, 0·35, 1·01, respectively. In contrast, the β-glucosidase immobilised in polyacrylamide gels was more resist-ant in proteolysis than that trapped in alginate beads. © 1998 Society of Chemical Industry     

铁盐共沉淀泡沫分离法去除水中铬离子

采用铁盐共沉淀泡沫分离法对水中的铬离子去除进行了研究,考察了pH值、Fe^2＋/Cr（Ⅵ）摩尔比、十二烷基苯磺酸钠（LAS）浓度、气液比等因素的影响.实验结果表明：当水中的铬离子含量为8 mg·L^-1时,去除率可达97.1%.根据泡沫分离过程与化学反应过程在物理行为上的类似性,引入等效的化学反应常数,对采用共沉淀泡沫分离法去除水中的铬离子进行宏观动力学研究.结果表明该泡沫分离过程可等效为一级反应,结合停留时间分布测定对该过程的数学模型进行了分析讨论.     

直链型偶氮苯聚氧乙烯醚稳泡剂的制备及表面活性

以4-羟基偶氮苯、1,2-二溴乙烷、PEG-600为原料,合成直链型偶氮苯聚氧乙烯醚非离子表面活性剂(PEP-600)。通过红外光谱和核磁共振氢谱表征了其结构,并测试了其表面活性。结果表明,PEP-600临界胶束浓度(CMC)为4.99×10~(–3) mol/L,在CMC处表面张力为48.09 mN/m,饱和吸附量为2.48×10~(–3) mmol/m~2,亲水亲油平衡值(HLB)为14.20。将PEP-600与0.1 g/L的十二烷基硫酸钠复配最大发泡比为12,泡沫半衰期为220s左右,直链型分子结构的PEP-600在泡沫液膜表面排列紧密,具有优异的起泡性能,可用作泡沫染整稳泡剂。     

Studies on the structure and formation mechanism of carbon gel in the carbon black filled polyisoprene rubber composite

The structure and formation mechanism of carbon gel in carbon black filled polyisoprene composites were studied by the pulsed NMR technique. The composites were prepared from a wide range of molecular weights by a solution blend. The carbon gels were extracted from the composites by a solvent-extraction method. The content of carbon gel was not governed by the molecular weight of rubber but was controlled by the viscosity of rubber solutions which were used for the blend. Three rubber phases, having different spin-spin relaxation times, were detected in all the carbon gels. The increase of carbon gel content in the composites was mainly from the increase of highly mobile rubber phase, and the gel became soft with the development of this phase. On the other hand, the content and structure of glassy rubber phases were not affected by the size of the carbon gel, and they showed almost a constant value despite the large change in the carbon gel content. A part of the highly mobile rubber phase in the gels could be removed by solvent extraction at high temperature. These results suggest that the formation of carbon gel is primarily governed by two factors: One is the well-known rubber-carbon black interaction, and the other is a physical crosslink between the carbon gel and unbound rubber molecules during blend. © 1996 John Wiley & Sons, Inc.