Preparation of Chitosan Magnetic Microspheres

用共沉淀法制备Fe3O4磁性纳米粒子,并对其用油酸进行表面改性,继而采用沉淀聚合法制备壳聚糖磁性微球。考察了沉淀剂浓度、乳化剂种类、Fe3O4的改性等条件对制备微球的影响。应用扫描电镜、红外谱图、接触角仪、粒径分析仪及磁铁吸附对壳聚糖磁性微球的形态与特性进行了表征。研究结果表明,在适宜的沉淀剂浓度、复合乳化剂、Fe3O4经油酸改性等条件下,可以制得平均粒径为150 nm、单分散性好且磁性明显的壳聚糖磁性微球。The Fe3O4 nanoparticles were prepared by co-precipitation method and modified by oleic acid.Chitosan magnetic microspheres were then prepared by precipitation polymerization method.The results demonstrated that the concentration of the precipitant,the type of emulsion and the modification of the iron oxide were the most effective parameters for the preparation of the microspheres.The SEM,IR and DLS results indicated that the diameter of the microspheres was about 150nm and the microspheres were uniformly distributed.The magnetic test showed the microspheres were magnetic sensitive.国家自然科学基金(50573063);; 教育部新世纪优秀人才计划项目;; 高等学校博士点专项基金(2005038401);; 厦门大学人才基金(0000X071C1

Experimental studies on treating humid acid solution by photocatalytic oxidation

以腐殖酸类物质作为废水中有机物的代表,研究了水体中腐殖酸在纳米TIO2颗粒上的吸附行为及以此为催化剂对水中腐殖酸进行的光催化氧化行为。考察了不同催化剂质量浓度、初始PH值、腐殖酸初始质量浓度等因素对腐殖酸去除率的影响。结果表明:腐殖酸在TIO2颗粒上的平衡吸附量对溶液的初始PH值依赖性很小;初始PH值降低、腐殖酸初始质量浓度减小,均能显著提高腐殖酸的去除率。同时将光催化氧化与单纯紫外线照射的去除率作对比,光催化氧化法明显优于单纯紫外线照射。Humid acid(HA) is the representation of organic matter in wastewater.The behaviors of adsorption and photocatalytic oxidation of HA in water on TiO2 particles were studied.The effects of different factors on removal of HA from water were investigated,such as mass concentration of catalyst,initial value of pH,initial mass concentration of HA,etc.The results show that the adsorption amount of HA in balance on TiO2 particles is independent of initial pH value of the solution.The removal efficiency of HA is improved greatly with the decreasing of initial pH value and initial mass concentration of HA.Comparing the removal efficiency of photocatalytic oxidation with that of ultraviolet radiation alone,the photocatalytic oxidation is better than ultraviolet radiation alone.厦门大学人才引进基金项目(0000X071C1

Preparation of agricultural low-cost super water absorbent

概述了合成类吸水树脂在农用上的进展,提出采用低成本且工艺成熟的水溶液法,以丙烯酸(AA)、丙烯酰胺(AM)为基体、接枝可溶性淀粉进行三元单体共聚,经钠基膨润土改性,复合引发剂、复合交联剂制备低成本、易降解的合成类吸水性树脂。经实验改进和工艺条件优化后,树脂吸去离子水倍率可达1 940.9 g/g,吸自来水899.8g/g。采用红外光谱仪、热重分析仪、扫描电镜、X射线衍射仪等分析手段对合成树脂进行了分析表征,证实了产物为淀粉、丙烯酸及丙烯酰胺的共聚物。The utilization status of the synthetic absorbent resin in agricultural applications was summarized.An improved process of three monomer copolymer system was proposed by using an aqueous solution polymerization.These three monomers are soluble starch,acrylic acid and acrylamide,which are modified by sodium bentonite,using a composite initiator and cross-linker.By improving the experiments and optimizing the process conditions,the absorption rate of the synthetic absorbent resins is up to 1 940.9 g/g in deionized water,and 899.8 g/g in tap water.In addition,the structure and performance of the synthetic absorbent resin were characterized by using infrared spectroscopy,thermal gravimetric analysis,scanning electron microscopy and X-ray diffraction,which shows that it is an copolymer of starch,acrylic acid and acrylamide

Optimization of Hydrometallurgical Purification for SiO_2 in the Process of Preparing Solar-grade Silicon

考察了Hf质量分数、H2C2O4质量分数、HnO3质量分数、酸浸时间、粒径、液体质量与固体质量的比值(简称液固比,下同)等因素对混酸法提纯SIO2工艺过程的影响,利用电感耦合等离子体发射光谱仪(ICP-OES)、场发射扫描电子显微镜(SEM)进行表征。结果表明,最佳工艺条件为:W(Hf)=2%、W(H2C2O4)=3%、W(HnO3)=30%、酸浸时间4 H、粒径100~120目、液固比4∶1、酸浸温度30℃。fE、Al、CA、P杂质的去除率分别达到99.99%、14.02%、73.27%、60.00%,经混酸法处理后SIO2中杂质总量的质量分数降至1.465x10-4。As a pre-treatment unit for preparing solar-grade silicon,hydrometallurgical route could remove most metallic impurities in silicon dioxide(SiO2) and raise the yield of the final product.Acid leaching of SiO2 could reduce the cost and energy consumption of industrialized development.Combined with high purity of reducing agent,the successor process of pyrometallurgy can also achieve "continuous casting".Factors such as the mass fraction of leaching agent,time,the particle size of SiO2,and the liquid-solid ratio were investigated,and the samples were characterized by means of ICP-OES,SEM,etc.The optimal reaction conditions were as follows:w(HF)=2%,w(H2C2O4)=3%,w(HNO3)=30%,reaction time 4 h,the average size of SiO2 powder particle 100～120 mesh,the liquid-solid ratio 4∶1,and room temperature 30 ℃.It was found that the final removal rates of impurities of Fe,Al,Ca,P could reach 99.99%,14.02%,73.27%,and 60.00% respectively and the mass fraction of total amount of impurities could be reduced to 1.465×10-4

丝组二肽——现代蛋白酶分子进化过程中的原始雏形

系统阐述了我们实验室近十五年来对丝组二肽的生物活性的研究.丝组二肽是目前报道的具有多种切割活性的最小活性肽,它不仅能够切割DNA,而且可以切割蛋白质及羧酸酯.丝组二肽是迷你的磷酸酯酶和蛋白水解酶,是现代蛋白酶分子进化过程中的原始雏形

Development and fluidized simulation of semi-continuous pilot reactor for carbon nanotubes preparation

第一作者：朱丽（1980—），女，硕士研究生，从事化工过程开发与设计研究。E-mail:[email protected]。联系人：汤培平，教授。E-mail:[email protected]。[中文文摘]在间歇过程的碳纳米管制备实验基础上结合经验公式,开发设计了制备碳纳米管的半连续中试流化床反应器,结果表明:催化剂100 g、反应温度650℃时,甲烷平均转化率23.2%,碳纳米管产率为177.5 g/h,操作周期为间歇反应器的1/3,反应器可较好地实现碳纳米管制备功能。用计算流体力学方法对此反应器内的气固两相流化行为进行数值模拟,得到在工况条件下,最佳的催化剂用量为100 g、操作气速为0.15 m/s等工艺参数。[英文文摘]Semi-continuous pilot test fluidized bed reactor for carbon nanotubes preparation was designed and fabricated,base on experiments of batch fluidized bed reactor and repeated calculations.When reaction temperature is 650 ℃,reaction time is 4 h,velocity of CH4,H2,N2 are 0.1m/s,0.008 m/s,0.016 m/s,the yield of carbon nanotubes is 177.5 g/h,conversion of CH4 is 23.2%,production cycle is shortened by 2/3.The fluidization behavior of gas-solid fluidization process was calculated by using the computational fluid dynamics(CFD) package Fluent6.1.And the optimal condition for carbon nanotubes is that the velocity of CH4 is 0.1m/s,and catalyst is 100g

Comparison of efficacy between mPCNL with holmium laser and EMS standard tract PCNL in the treatment of complex renal calculi under ultrasound guidance

目的比较b超引导下微通道经皮肾镜钬激光碎石术(MPCnl)与标准通道经皮肾镜气压弹道联合超声碎石术(标准通道PCnl)治疗复杂性肾结石的临床疗效。方法对78例复杂性肾结石患者分别行MPCnl(35例)和标准通道PCnl(43例)治疗,术后对2组患者的手术时间、一期结石清除率和手术并发症等指标进行比较分析。结果 2组患者分别成功建立16f和24f经皮肾通道并一期行碎石术。MPCnl组手术时间明显长于标准通道PCnl组;一期结石清除率MPCnl组低于标准通道PCnl组,差异均具有统计学意义(P均38.5℃1例。2组并发症差异无统计学意义(P>0.05)。结论 b超引导下MPCnl与标准通道PCnl治疗复杂性肾结石安全有效、并发症发生率低,标准通道PCnl联合应用EMS第4代气压弹道联合超声碎石清石系统碎石清石效率高,较MPCnl钬激光碎石明显有优势,值得推广。Objective To compare the outcomes of the surgical treatment of complex renal calculi with minimally invasive percutaneous nephrolithotomy(mPCNL) and EMS percutaneous nephrolithotomy(standard tract PCNL) under ultrasound guidance.Methods A total of 78 patients with complex renal calculi were allocated to either mPCNL treatment group(mPCNL group,n=35) or EMS(swiss,the fourth generation) standard tract PCNL treatment group(standard tract PCNL group,n=43).The operative time,primary stone-free rate and operative complications in the two groups were compared.Results 16F and 24F percutaneous renal accesses were successfully established in mPCNL group and standard tract PCNL group respectively,and then the first lithotrity-lithiasis cleaning procedure was performed.The operation time in mPCNL group was longer than that in the standard tract PCNL group 〔(102±31) min vs(67±22) min,P38.5 ℃ occurred in one case of mPCNL group.There was no significant difference in operative complications in two groups(P>0.05).Conclusions Both the treatments of complex renal calculi with mPCNL and EMS(the fourth generation) standard tract PCNL under ultrasound guidance are similarly safe,but the standard tract PCNL has the superiority of higher primary stone-free rate and shorter operation time over the holmium Laser mPCNL.Therefore the standard tract PCNL merits propagation for treating complex renal calculi

Characterization and immunoprotective effect of SjIrV1,a 66 kDa calcium-binding protein from Schistosoma japonicum

钙结合蛋白是日本血吸虫生长发育不可缺少的蛋白,具有非常广泛而重要的功能。在课题组日本血吸虫体被表膜蛋白研究基础上,利用PCr技术克隆了中国大陆株日本血吸虫66 kdA钙结合蛋白(SJIrV1)编码基因的CdnA序列,blAST分析与菲律宾株日本血吸虫SJIrV1 CdnA编码序列一致,荧光定量PCr分析表明该基因在童虫和成虫期不同发育阶段均有表达,其中在35 d和42 d成虫中表达量较高,在42 d雌虫中该基因表达水平远高于42 d雄虫。构建重组表达质粒PET28A(+)-SJIrV1,在大肠杆菌中成功诱导表达,重组蛋白主要以可溶性形式存在,通过高效液相色谱法(rP-HPlC)以及串联质谱法(MS/MS)鉴定所获蛋白为目的蛋白SJIrV1。蛋白质印迹(WESTErn blOTTIng)分析结果显示重组蛋白能被感染日本血吸虫鼠血清和免疫鼠血清所识别,SJIrV1蛋白在虫体各发育阶段中均表达。免疫荧光染色实验观察表明SJIrV1主要分布在日本血吸虫成虫的表膜。应用重组蛋白免疫bAlb/C小鼠后,免疫鼠血清中检测到较高水平的特异性Igg、Igg1和Igg2A抗体。结果表明SJIrV1可能在日本血吸虫的生长发育过程中起着重要作用。Calcium-binding protein is an indispensable protein which performs extensive and important functions in the growth of Schistosoma japonicum.Based on our primary study on tegument surface proteins of S.japonicun,a cDNA encoding a 66 kDa calcium-binding protein of S.japonicum(Chinese strain) was cloned,sequence analysis revealed that it was identical with that of SjIrV1 of Philippines strains S.japonicum.The expression of SjIrV1 were detected by Real-time PCR,using cDNA templates isolated from 7,14,21,28,35 and 42 days worms and the results revealed that the gene was expressed in all investigated stages,and the mRNA level of SjIrV1 is much higher in 42 d female worms than that in 42 d male worms.The cDNA containing the open reading frame of IrV1 was subcloned into a pET28a(+) vector and transformed into competent Escherichia coli BL21 for expression.The recombinant protein was purified using a Ni-NTA purification system,and confirmed by high performance liquid chromatography(RP-HPLC) and tandem mass spectrometry(MS/MS).Western blotting analysis showed that recombinant SjIrV1(rSjIrV1) could be recognized by the S.japonicum infected mouse serum and the mouse serum specific to rSjIrV1,respectively.Immunofluorescence observation exhibited that SjIrV1 was mainly distributed on the tegument of the 35-day adult worms.ELISA test revealed that IgG,IgG1 and IgG2a antibodies are significantly increased in the serum of rSjIrV1 vaccinated mice.The study suggested that rSjIrV1 might play an important role in the development of S.japonicum.国家自然科学基金(No.31172315); 上海科技发展基金(No.12140902700); 中国博士后科学基金(No.2012M510630)资助~

催化裂解法制备碳纳米管中试反应器优化研究

对催化裂解法(CVD)间歇制备多壁碳纳米管(CNTs)的中试流化床反应器的结构进行优化研究,以期简化结构、改变出料方式、实现半连续化操作。实验结果表明:床层内置加热器开启,CNTs产量下降15%,床层阻力增加67%;预热层高度为零,反应4h,产率最高为9.2g/g;催化剂量为100g,最佳匣钵高度是35cm;将间歇操作调整为半连续操作,生产周期将从24.0h降为8.5h