90 research outputs found
Treatment of Purified Terephthalic Acid Wastewater by Sequencing Batch Reactor
[中文文摘]采用序批式反应器(SBR)处理模拟精对苯二甲酸(PTA)废水,考察了曝气量、沉降时间、进水方式等对对苯二甲酸(TA)生物降解效果的影响。实验结果表明,对于TA质量浓度小于1 500m g/L的废水,采用完全曝气SBR运行4h,TA和COD的去除率均能达到95%以上,TA平均去除速率随TA浓度的增加而增大。TA质量浓度为1 500m g/L时,曝气量、沉降时间和进水方式是影响其降解效果的主要因素。采用SBR处理高浓度PTA废水可克服污泥膨胀和抗冲击负荷能力弱的问题,且系统的稳定性和PTA废水的处理效果较好。[英文文摘]Simulated purified terephthalic acid(PTA)wastewater was treated by sequencing batch reactor(SBR).The effects of aeration rate,settling time,feeding mode on the biodegradation of terephthalic acid(TA)were investigated.When the mass concentration of TA is less than 1 500mg/L,the removal rate of TA and COD are both more than 95% after aerating for 4h in SBR.The average TA removal rate increases with the increasing of TA mass concentration.When the mass concentration of TA is 1 500mg/L,the main factors affec ting degrada tion are aeration rate,
settling time and feeding mode. Treating high concentration PTA was tewater by SBR can solve the problems of sludge bulking and lack of shock load resistance cap ability, and the system has a good stability and treatment effect for
PTA wastewater.国家自然科学基金资助项目(20076037
Removal of Iron During Copper Sulfate Production from Bioleaching Reextraction Solution
[中文文摘]利用三种方法分别对某铜矿山生物浸铜反萃液生产饲料级五水硫酸铜的重要步骤———除铁工艺进行了深入研究,结果表明:采用黄铵铁矾法除铁,控制温度在95℃、pH=1 6,除铁率可以达到91 2%;采用氢氧化铁沉淀法,于70℃,pH=3 8的条件下,除铁率可达98 1%。但上述方法除+、Na+和Ca2+等杂质带入硫酸铜溶液;采用一步结晶法,控制结晶温度在60℃、结铁过程会将NH4晶时间为6h,除铁率可以达98 5%,该工艺操作简单,产品符合饲料级硫酸铜的国家标准。[英文文摘]Iron removal is crucial to the process of feed-additive copper sulfate pentahydrate production from bioleaching reextraction solution.In this paper,three iron removal methods were examined.A series of experiments were conducted in different conditions and the results indicated that when iron was removed by precipitating in the form of ammonium jarosite(95 ℃,pH=1.6),the iron removal efficiency was 91.2%,while by precipitating in the form of ferric hydroxide(70 ℃,pH=3.8),the iron removal efficiency was 98.1% However ,by these two methods ,the use of oxidant and neutralization reagents introduced unwanted
NH+4 ,Na + ,Ca2 + into copper sulfate solution. Crystallizating copper sulfate from reextraction solution ,a simple
process ,could remove iron effectively without adding any additives and the iron removal efficiency could reach 98.5% under the condition of 60 ℃and 6 h ,and the quality of copper sulfate met national standards of feed additive.福建紫金矿业股份有限公司资助项
Biosynthesis of Silver Nanoparticles from Various Medicinal Plant Extracts and Their Antibacterial Properties
作者简介:林源(1985-),女,硕士研究生。联系人:李清彪(1963-),教授,博士生导师,电话:0592- 2189595,E-mail:kelqb@xmu.[中文摘要]分别以中草药丁香、山茱萸、地榆和乌梅的提取液为还原剂和保护剂合成银纳米颗粒,利用紫外-可见吸收光谱(UV-vis)、透射电镜(TEM)以及X射线粉末衍射(XRD)对产物进行了表征。结果表明,所得银纳米颗粒呈近球形,提高提取液的pH有利于获得粒径较小、分散性好、稳定性高的银纳米颗粒。进一步考察制得的银纳米颗粒的抗菌性能,结果表明,其对大肠杆菌和金黄色葡萄球菌有很强的抑制作用,最小抑菌质量浓度(M IC)分别可达1.69和3.38 mg/L。[英文摘要]Quasi-spherical silver nanoparticles(AgNPs) were synthesized from the extracts of different medicinal plants including Syzygium aromaticum,Cornus officinalis,Prunus mume and Sanguisorba officinalis,and were subsequently characterized by means of UV-visible spectroscopy,transmission electron microscopy and X-ray diffraction.When pH values of the extracts were adjusted to 10,the biosynthesized AgNPs were well-dispersed,highly stable,and relatively small in size.Thus obtained AgNPs were found to demonstrate good antibacterial activity against Escherichia coli and Staphylococcus
aureus,with minimum inhibitory concentrations of 1.69 and 3.38 mg /L required,respectively.国家自然科学基金重点项目(21036004);国家自然科学基金面上项目(20976146);福建省科技计划重点项目(2009H0041
改良分子信标-双重实时荧光PCR快速检测SARS病毒
目的建立改良分子信标-双重实时荧光PCR检测SARS病毒的方法,用于SARS的早期诊断和动物溯源。方法利用改良分子信标技术、装甲RNA和双片段双色荧光技术,根据GenBank公布的SARS病毒聚合酶基因1b的阅读开放框架结构的保守序列,自行设计一对引物和探针,以部分临床标本的酶联吸附实验结果和传统细胞培养方法作为对照,建立分子信标检测SARS病毒的方法。对368份临床标本(咽漱液、血液、粪便、尿液)、52份细胞培养液和50份动物标本进行荧光PCR扩增。结果分子信标检测SARS病毒的方法灵敏度为10~100个拷贝ml,与流感病毒等呼吸道病毒无交叉反应。分子信标检测368份临床标本,20份阳性。其中确诊病例阳性率为21.27%(1047),确诊病例的咽漱液阳性率为43.48%,还分别从粪便和血清中检测到SARS病毒。52份细胞培养液,29份阳性,阳性率为55.77%。50份动物标本,23份阳性,阳性率为46%。结论改良分子信标-双重实时荧光PCR检测SARS病毒方法灵敏度高、特异性强,可用于SARS的临床早期诊断和动物溯源
森林对径流影响研究的回顾与展望
论文简要回顾了森林水文学的研究历史,并重点介绍了在森林水文学研究中居于重要地位的森林集水区研究的起源与发展, 分析了这一研究方法的特点, 并对主要研究结果进行了比较。大多数研究结果显示, 去除森林可以使径流量增加, 但森林与水的关系极其复杂, 森林对径流量的影响因地域、 森林类型以及森林管理方式等因素的不同而存在差异; 在评价森林对流域径流量的影响时应全面考虑, 分析各地区之间的差别, 一个地区所得的结果不能作为森林生态系统水文功能的普遍规律而在其它条件不同的地区加以应用。今后应加强合作研究,特别是利用网络研究对比不同集水区之间的结果来探讨森林对径流的影响,同时重视新技术和新方法的应用
中等视场大相对孔径水下两档变焦光学系统
研究了水下两档变焦光学系统的设计方法并给出了具体设计实 例。采用轴向移动变焦方式,变焦过程中相对孔径保持不变,相对孔径为1/1.4,系统变焦比为2,在水下的宽视场角为60,°有效焦距3.6 mm,用于大范围内搜索目标;窄视场角为20°,有效焦距7.2 mm,用于对目标进行具体分析。在空间42 lp/mm处的宽视场和窄视场的光学传递函数值均大于0.4,成像质量较好。既满足了水下成像对大相对孔径和较大视场的要求,又能够在大范围内搜索目标, 小范围内对具体目标进行分析,满足实际应用的需要
一种曝光可控折转式双波段成像系统设计
设计一种工作波段可切换,曝光时间从0.1s~99.9s可 控,操作方便的折转式1∶1成像系统,通过转向棱镜连接前后镜组,替换不同厚度的滤色片以实现双波段成像。该系统将高分辨率折转式1∶1成像镜头与电子快 门结合,光学系统视场范围φ17mm,分辨率达到8μm,工作距离55mm,系统用转向棱镜折转90°成像,克服了一般镜头本身不能控制曝光时间的缺点, 使曝光时间和光的导向能够精确控制,改善了化学发光免疫分析的试验条件,有望在临床中的化学发光免疫分析,以及环境科学、光化学等领域得到应用。
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