氨基化碳纳米管在神经修复作用中的研究进展

超支化聚合物为碳纳米管的功能化研究提供了一种新方法,功能化的碳纳米管具有良好的分散性和生物相容性,能有效携载药物或基因,为中枢神经系统疾病的治疗提供了新思路。氨基是一种常见的修饰基团,载体可以通过酰胺键方便地携带药物,因此碳纳米管表面氨基化具有广泛的应用前景。氨基化碳纳米管具有溶解性好、反应活性高和细胞毒性低等特点,为其在医药领域的应用奠定了基础。     

无机晶须材料的制备方法和应用进展

无机晶须是一种用途广泛的新型功能材料,在塑料改性等方面具有广泛的应用前景。介绍了晶须的制备方法以及几种常见无机晶须的研究和应用情况,提出了其今后的发展前景。     

RNAi技术在昆虫防控研究中的应用和发展前景

随着昆虫分子生物学技术的蓬勃发展,RNA干扰(RNAi)作为21世纪以来的变革性技术,通过特异性抑制靶基因转录后水平的表达,在昆虫基因功能研究方面被广泛应用。由于沉默重要基因的表达会导致某些昆虫的死亡或行为缺陷,故该技术被认为是一种潜在的害虫防治策略,在控制、研究甚至保护昆虫方面具有巨大潜力,目前已被广泛应用于半翅目、直翅目、双翅目等昆虫。RNAi是昆虫学研究和害虫控制潜在应用的流行和重要的反向遗传学策略。从RNAi技术的原理、导入方法、效率影响因素及在农业害虫中的应用研究实例等4方面进行了综述,并对其防控应用和发展前景进行了展望。     

噬菌体展示疫苗的研究进展

噬菌体是感染细菌、真菌、放线菌和螺旋体等微生物的病毒,因其固有的免疫原性、遗传可塑性、稳定性及安全性等优势,使其在疫苗研发中具有独特的潜力。目前,有较多利用其构建疫苗递送平台的研究,主要包括噬菌体展示疫苗、噬菌体DNA疫苗及杂交噬菌体DNA疫苗3种形式,其中研究最为广泛的是噬菌体展示疫苗。噬菌体展示技术是一种新型疫苗制备技术,是以噬菌体为载体,通过将外源多肽或蛋白基因整合至噬菌体基因中,以融合蛋白的形式展示在噬菌体表面的分子生物学技术。本文主要就噬菌体展示疫苗的免疫学基础、展示系统及其在疾病预防应用的研究进展作一综述,以期为噬菌体展示疫苗的研发与应用提供参考。     

氟氯苯胺在农药中的开发利用前景

氟氯苯胺又称3-氯-4-氟苯胺,因氟氯苯胺分子结构中同时含有-NH2和-X卤代基两种活性基因,能参与多种化学反应,使其在农药工业方面具有广泛的应用。氟氯苯胺可以氟苯、硝基苯、邻二氯苯、     

DOPE嵌入式阳离子脂质体介导基因转运研究

二油酰磷脂酰乙醇胺(DOPE)是应用最广泛的中性磷脂,作为非病毒基因载体的重要组成部分,具有很强的细胞膜去稳定化作用,克服了阳离子脂质体高细胞毒性、制备困难、缺乏稳定性等缺点,在介导基因转运方面具有广阔的应用前景。在近年来DOPE嵌入阳离子脂质体介导基因转运研究的基础上,论述了DOPE嵌入阳离子脂质体的作用方式和在介导基因转运方面的研究现状,并展望了DOPE嵌入式阳离子脂质体的发展方向。     

细菌基因敲除策略及其在维氏气单胞菌研究中的应用

基因敲除技术是20世纪80年代发展起来的一种分子生物学技术,目前已广泛应用于微生物基因功能等相关领域的研究中。维氏气单胞菌(Aeromonas veronii,A. veronii)是气单胞菌科气单胞菌属的一种,近年来,该菌引发疾病的报道逐年增多,因此,对其致病机制的研究显得尤为重要。本文对细菌不同基因敲除策略及其在A. veronii基因功能研究中的应用作一综述,旨在为A. veronii致病机制的深入研究提供参考。     

树枝状大分子用于药物载体的研究进展

树枝状大分子是近年来出现的一类新型合成纳米高分子,具有可控的三维高度支化结构、表面分布着大量的功能基团和单分散等特点,使其在生物医学等领域中日益受到广泛关注。作为一种新型非生物载体,树枝状大分子内部空腔和表面功能基团均可与药物复合,在药物输送和基因转运等方面具有广阔的应用前景。     

原子力显微镜在高分子研究中的应用

原子力显微镜(AFM)作为一种新型纳米显微技术,具有分辨率高、样本制作方便等优点,在高分子研究中获得广泛的应用,本文综述了其在高分子研究领域中的一些应用进展。     

基于低温等离子体的苯直接氧化制备苯酚的研究进展

苯酚作为一种应用非常广泛的重要化工原料,其绿色制备方法成为近年来一大研究热点。低温等离子体具有操作简单、成本低廉等优点,在苯直接氧化制备苯酚领域得到了广泛研究与应用。本文介绍了低温等离子体促进有机反应的原理,重点对其在苯直接氧化制备苯酚方面的应用进行了综述,并讨论了该领域存在的问题和解决思路,最后对其发展前景进行了展望。     

多拷贝脑钠肽基因表达质粒的构建及其表达

目的构建多拷贝脑钠肽(BNP)基因重组表达质粒,并探讨BNP基因的拷贝数与其表达水平的相关性。方法通过人工合成和PCR技术扩增BNP基因,将其克隆至载体pCW111中,构建表达质粒pBNP11,并通过亚克隆构建含有不同数量表达盒的正向串联表达质粒,分别转化大肠杆菌DH5α和BL21(DE3),经温度诱导表达,SDS-PAGE分析,并经激光扫描测定目的蛋白的表达量。结果测序及酶切鉴定证明1～3拷贝BNP重组表达质粒构建正确,重组蛋白在大肠杆菌DH5α和BL21(DE3)中均可获得表达,表达量分别为菌体总蛋白的8.12%、9.94%、和9.18%。结论已构建了多拷贝BNP的重组表达质粒,BNP的表达水平随BNP拷贝数的增加而升高,但并未成倍增加。     

白细胞介素-10基因多拷贝表达盒的构建及在毕赤酵母中的表达

目的构建白细胞介素-10(IL-10)基因多拷贝表达盒,提高IL-10在毕赤酵母中的表达水平。方法体外构建重组表达载体αIL-10/pAO815,BamHⅠ和BglⅡ双酶切获得目的基因表达盒(AOX-αIL-10),再连接到BglⅡ酶切位点处,依次构建多拷贝重组载体n(AOX-αIL-10)/pAO815。从质粒pPIC9K上用NdeⅠ和SalⅠ双酶切获得Kan抗性基因,重组到多拷贝表达载体n(AOX-αIL-10)/pAO815上。重组载体n(AOX-αIL-10)/pAO815电转化毕赤酵母,PCR筛选含有IL-10基因的酵母转化子,甲醇诱导表达,对表达量高的转化子再次经重组载体n(AOX-αIL-10)/pAO815-Kan电转化,高浓度G418抗性筛选二次酵母转化子,使用甲醇诱导表达。ELISA测定IL-10含量,MC/9细胞测定IL-10活性。结果所构建的8拷贝表达盒的重组载体8(AOX-αIL-10)/pAO815和4拷贝表达盒4(AOX-αIL-10)/pAO815-Kan,转化子分泌表达IL-10水平最高,为(8.25±1.65)mg/L,比活性为1.465×105U/mg。结论已成功构建了高拷贝表达盒,并提高了IL-10在毕赤酵母中的表达水平。     

Investigation of Filter Bypass Leakage and a Test for Aerosol Sampling Cassettes

Plastic filter cassettes (37 and 25 mm), which are press fitted together to seal and hold a filter in place, are commonly used for sampling aerosols. Aerosol bypass leakage around the filter has been reported by several researchers and attempts have been made to test for leakage and to reduce the likelihood of leakage by improving cassette design. Under typical sampling conditions, there is often no indication to the user that leakage may have occurred. In the present study, a particle count leak test was developed that used a particle counter that measured the particle number concentration of ambient aerosol (primarily submicrometer particles) upstream and downstream of the filter cassette. The relationship between leak test results and particle loss from the filter depended on particle size and type in a complex fashion. The mechanisms of particle loss were investigated and the losses increased for particles above 2 w m and were much greater for solid and fume aerosols than for oil droplets. Although the test could not be used to predict particle mass loss during sampling, the test was a sensitive indicator of cassette bypass leakage and was used to establish compression pressures needed for proper assembly of these cassettes.     

基于SCPI指令集的测量仪器应用层驱动程序开发

在.NET编程环境中,使用C#语言开发了基于SCPI指令集的可编程信号源E8267D应用层驱动程序。通过这个具体开发实例,可以迅速掌握基于SCPI指令集的可编程工业测量仪器应用层驱动程序的通用开发技巧,进而轻松掌握工控设备应用层驱动程序的开发方法,为实现工业控制和工业测量工作的自动化奠定坚实的基础。     

负载型氨分解催化剂的载体——高岭土的研究

为了拓展高岭土在化工领域的应用,研究了将其作为催化剂载体应用于氨分解的可行性。通过正交实验确定了高岭土载体制备过程中最大影响因素,进而确定最佳制备条件。将其制备成负载型Ni基催化剂,进行氨分解活性评价,结果表明,与工业MgO载体比较,自制高岭土载体可以达到工业MgO载体的同等水平,在氨分解反应中可替代工业MgO载体。     

A Novel Multifilter PM10–PM2.5 Sampler (MFPPS)

A novel multifilter PM₁₀–PM_2.5 sampler (MFPPS) that enables the collection of four PM₁₀ and four PM_2.5 samples simultaneously has been developed and tested. The MFPPS uses a PM₁₀ impactor as the inlet and operates at 33.4 L/min. After the inlet, the aerosol flow is divided half by a Y-type fitting. Half of the flow is directed into four PM₁₀ filter cassettes, while the other half is directed into four PM_2.5 filter cassettes after the aerosols are further classified by a PM_2.5 impactor. An active flow control system consisting of two mass flow controllers (MFCs), one for PM₁₀ and the other for PM_2.5, is used to fix the total flow rate of 16.7 L/min for four PM₁₀ or four PM_2.5 channels based on the ambient pressure and temperature. To ensure flow rate uniformity through each of the four PM₁₀ or four PM_2.5 filter cassettes, an orifice is assembled behind each of the filter cassettes to increase the pressure drop, such that the flow rates of eight sampling lines are nearly equal using just two MFCs. The MFPPS was calibrated in the laboratory for particle collection efficiency curves first. Then, the ambient PM concentrations were compared with those of other two collocated FRM samplers, the dichotomous PM₁₀ and the EPA WINS PM_2.5 sampler in the field study. Calibration results showed the cutoff aerodynamic diameters of the PM₁₀ and PM_2.5 impactors were 9.8 ± 0.1 and 2.5 ± 0.05 μm, respectively. Field comparison results indicated PM₁₀ and PM_2.5 concentrations agreed well with the other two PM samplers.     

Calculation of Leakage and Particle Loss in Filter Cassettes

Experimental evidence of aerosol bypass leakage around the filter in plastic filter cassettes prompted an investigation using computational fluid dynamics to explain particle penetration through the leak. Axi-symmetric models of a cassette with several leak dimensions were constructed. The models predicted that submicrometer particles penetrated the leak, but that larger particles impacted on the filter surface. Experimental data from another study clearly indicated that larger solid particles were being lost from the surface of the filter during sampling. When particle bounce was invoked as an explanation for this loss of sampled solid particles, the theoretical loss from the filter in cassettes with large leaks exhibited characteristics similar to the experimental data. For small leaks, the mass loss behavior appeared to be more complex.     

抗新型冠状病毒抗体样本盘在其胶体金测试卡质量评价中的应用

目的建立抗新型冠状病毒(SARS-CoV-2)抗体样本盘,并应用于SARS-CoV-2抗体胶体金测试卡的质量评价。方法采用新型冠状病毒肺炎(Corona Virus Disease 2019,COVID-19)康复者恢复期经病毒灭活的血浆样本建立SARS-CoV-2抗体样本盘,并进行优化。收集国内3个厂家(厂家S、厂家L、厂家H)胶体金测试卡,分别检测样本盘,并提出改进意见,厂家优化改进后,对优化后测试卡进行评价和比较。结果厂家S优化前测试卡的准确度为92.54%,灵敏度为90.78%,特异性为100.00%,约登指数为0.908,但阳性检测线颜色浅,不易辨识;优化后测试卡的灵敏度为95.35%,特异性为98.91%,准确度为97.19%,约登指数为0.943,且显色明显,易于判读。厂家L优化前测试卡检测IgM抗体的灵敏度仅为14.28%,漏检率较高,且显色不明显;优化后测试卡检测IgM抗体的的灵敏度达98.63%,显色明显且快速。厂家H测试卡检测IgG抗体的灵敏度为98.08%,特异性为100.00%,准确度为98.90%,约登指数为0.981;检测IgM抗体的灵敏度为84.50%,特异性为86.49%,准确度为85.71%,约登指数为0.710。结论本实验建立的SARS-CoV-2抗体样本盘可用于SARS-CoV-2抗体检测试剂的质量评价。     

Modelling and optimisation of a chemical industry wastewater treatment plant subjected to varying production schedules

Industrial wastewater treatment plants (WWTPs) have to provide 100% reliability and availability for the discharging facilities at an industrial site. Varying production schedules at these facilities and specific components occurring in the industrial wastewater considerably hinder the optimisation of industrial WWTPs. In this context it is shown in this paper that model‐based optimisation is an efficient and cost‐reducing way to ensure that an industrial WWTP functions well. The aim of the study presented was two‐fold. The first step was to show the usefulness of a proposed procedure to build and calibrate a model for the industrial WWTP. The second objective was to use the model for optimisation of the WWTP. As an example, a large set of possible production schedules in the different discharging facilities was simulated. Based on these simulations it could be predicted which schedules allow the effluent standards to be met and which do not. The calibrated and validated model was also used to investigate different operating strategies such as the in‐series operation of the two available aeration tanks. In fact, with the model it was shown that a 20% reduction of the degradable COD concentration in the effluent could be achieved by operating the tanks in series instead of in parallel. This case study shows how the approach presented can lead to fast and cost effective modelling and optimisation of an industrial WWTP. Copyright © 2004 Society of Chemical Industry     

Evaluation of procedural modifications to reduce glutaraldehyde vapors during the disinfection of endoscopes using three sampling methods

Glutaraldehyde is the preferred disinfectant for fiberoptic endoscopes. A number of studies have reported adverse health effects in workers exposed to glutaraldehyde vapors. High exposures can occur during the pouring and disposal of glutaraldehyde solutions. This study has tested the effectiveness of three procedural modifications designed to reduce exposures during these activities. These procedures were: (1) the use of a splash-resistant safety nozzle during the pouring of glutaraldehyde solutions, (2) the use of neutralizers during the disposal of glutaraldehyde solutions, and (3) the pouring of 14-day versus 28-day glutaraldehyde solutions. This study also evaluated three sampling methods to monitor glutaraldehyde vapors. The three methods evaluated were: (1) the OSHA method 64 using filter cassettes impregnated with 2,4-dinitrophenylhydrazine (DNPH); (2) DNPH-coated passive diffusion badges; and (3) a direct reading glutaraldehyde meter. Results showed that when the safety nozzle was not used during disinfection procedures, geometric means for all sampling methods were above the ACGIH TLV of 0.05 ppm (filter cassettes=0.105 ppm; passive badges=0.191 ppm; meter=0.082 ppm). Using the safety nozzle during the pour resulted in significant reductions in glutaraldehyde vapor concentrations (filter cassettes=0.014 ppm; passive badges=0.027 ppm; meter=0.021 ppm). Disposal of non-neutralized glutaraldehyde solutions resulted in peak vapor concentrations of up to 0.10 ppm. Neutralization prior to disposal reduced glutaraldehyde vapor concentrations to less than 0.01 ppm. Conclusive differences were not found when the pouring of the 14-day glutaraldehyde solution was compared to the pouring of the 28-day glutaraldehyde solution. Both solution pours resulted in vapor concentration means exceeding the TLV. Comparison of sampling methods showed no statistically significant differences between each method pair or when all methods were compared simultaneously. For the detection of glutaraldehyde vapors, the meter was as sensitive and as accurate as the filter cassettes. In conclusion, employees can significantly reduce exposures to glutaraldehyde vapors by using these modified pouring and disposal procedures, and the meter examined in this study provides an optimal method to measure glutaraldehyde vapors.