Clean-up and disposal process of polluted sediments from urban rivers

In this paper, the discussion is concentrated on the properties of the polluted sediments and the combination of clean-up and disposal process for the upper layer heavily polluted sediments with good flowability. Based on the systematic analyses of various clean-up processes, a suitable engineering process has been evaluated and recommended. The process has been applied to the river reclamation in Yangpu District of Shanghai City, China. An improved centrifuge is used for dewatering the dredged sludge, which plays an important role in the combination of clean-up and disposal process. The assessment of the engineering process shows its environmental and technical economy feasibility, which is much better than that of traditional dredging-disposal processes.

Bench-Scale Testing of Zinc Ferrite Sorbent for Hot Gas Clean-up

Advanced integrated gasification combined cycle （IGCC） power generation systems require the development of high-temperature, regenerable desulfurization sorbents, which are capable of removing hydrogen sulfide from coal gasifier gas to very low levels. In this paper, zinc ferrites prepared by co-precipitation were identified as a novel coal gas desulfurization sorbent at high temperature. Preparation of zinc ferrite and effects of binders on pore volume, strength and desulfurization efficiency of zinc ferrite desulfurizer were studied. Moreover, the behavior of zinc ferrite sorbent during desulfurization and regeneration under the temperature range of 350-400 ℃ are investigated. Effects of binders on the pore volume, mechanical strength and desulfurization efficiency of zinc ferrite sorbents indicated that the addition of kaolinite to zinc ferrite desulfurizer seems to be superior to other binders under the experimental conditions.

Simultaneous Determination of Four Estrogens in Compost Based on Ultrasonic Solvent Extraction, Solid-Phase Extraction Clean-Up and Analysis by UHPLC-MS/MS

A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco® and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC KinetexTM 2.6 μm XB-C18 100 ÅLC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g-1 and 2 ng·g-1 for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively.

Thermo-controlled,self-released smart wood tailored by nanotechnology for fast clean-up of highly viscous liquids

Designing highly porous materials is of great importance for liquid separation,water purification,and disinfection,such as spill oil cleaning and recycling,seawater desalting,and oil/water separation.However,a remaining challenge is to produce porous materials with the characteristics of fast absorption,continuous directional transport,and self-release of viscous liquid.Herein,a functional cellulosic composite is reported by the chemical treatment and functionalization of wood resulting in a smart wood that can thermally selfrelease and separate high viscosity oil.The smart wood has a high absorption speed of 1398 mL/(m_(2)·s)(ethylene glycol)and a maximum absorption capacity of 47.2 g/g(chloroform)due to its intrinsic vertical micro/nanoscale channel structure,low tortuosity,and high porosity.Moreover,the switchable wettability is achieved by the surface coating of poly(N-isopropylacrylamide)on the porous wood,which enables the collection and removal of oil from the oil/water mixture.The high viscosity oil can be automatically released due to the passive oil release at room temperature.The release capacity of the smart wood remains above 91%after 15 cyclic tests.We envision that this functional smart wood could be extended to a wide range of applications in smart hydrogels,microfluidics,artificial drug release,and environmental restoration.

化学药品中的遗传毒性杂质的质量控制

药品中微量水平的遗传毒性物质具有引发肿瘤甚至癌症的风险,并且该致癌风险可能与剂量没有相关性。因此,目前各国监管机构要求对药品中遗传毒性杂质进行严格控制。本综述通过查阅国内外相关文献、指导原则,从监管机构对药品中遗传毒性杂质的监管策略、遗传毒性杂质来源、检测方法及清除策略4个方面进行了系统的总结综述。该综述为药品中遗传毒性杂质的控制/清除、检测提供了参考和依据。

Tool Path Generation for Clean-up Machining of Impeller by Point-searching Based Method

Machining quality of clean-up region has a strong influence on the performances of the impeller. In order to plan clean-up tool paths rapidly and obtain good finish surface quality, an efficient and robust tool path generation method is presented, which employs an approach based on point-searching. The clean-up machining mentioned in this paper is pencil-cut and multilayer fillet-cut for a free-form model with a ball-end cutter. For pencil-cut, the cutter center position can be determined via judging whether it satisfies the distance requirement. After the searching direction and the tracing direction have been determined, by employing the point-searching algorithm with the idea of dichotomy, all the cutter contact （CC） points and cutter location （CL） points can be found and the clean-up boundaries can also be defined rapidly. Then the tool path is generated. Based on the main concept of pencil-cut, a multilayer fillet-cut method is proposed, which utilizes a ball-end cutter with its radius less than the design radius of clean-up region. Using a sequence of intermediate virtual cutters to divide the clean-up region into several layers and given a cusp-height tolerance for the final layer, then the tool paths for all layers are calculated. Finally, computer implementation is also presented in this paper, and the result shows that the proposed method is feasible.

腔室清洗的单臂组合设备初始暂态调度

为了提升腔室洁净度,晶圆厂需对组合设备腔室进行清洗操作,从而提高晶圆的加工质量.考虑腔室清洗时间和晶圆驻留时间的约束条件下,本文研究了单臂组合设备的初始暂态调度问题.首先,提出了机械手的初始暂态活动规则,并对机械手活动序列进行描述,实现了系统的初始暂态可调度性;其次,对机械手在初始暂态和稳态的活动时间进行了建模;然后,根据系统的时间特性,建立了初始暂态调度的线性规划模型;最后,通过实例验证了该方法的有效性.与已有的虚拟晶圆方法相比,该调度方法能有效减少初始暂态的完工时间,提高了组合设备的晶圆生产效率.

Wavelength-tunable mode-locked Yb-doped fiber laser based on nonlinear Kerr beam clean-up effect

We demonstrate a novel approach to achieve wavelength-tunable ultrashort pulses from an all-fiber mode-locked laser with a saturable absorber based on the nonlinear Kerr beam clean-up effect.This saturable absorber was formed by a single-mode fiber spliced to a graded-index multimode fiber,and its tunable band-pass filter effect is described by a numerical model.By adjusting the bending condition of the graded-index multimode fiber,the laser could produce dissipative soliton pulses with their central wavelength tunable from 1040 nm to 1063 nm.The pulse duration of the output laser could be compressed externally to 791 fs,and the signal to noise ratio of its radio frequency spectrum was measured to be 75.5 dB.

煤仓侧壁清理装置气动系统设计与仿真

针对井下煤仓堵塞清理现状,设计了煤仓侧壁气动清理装置,并完成了煤仓侧壁气动清理装置气动系统原理图的设计;采用AMESim建模仿真软件对工作大臂气动回路进行了建模仿真,并研究了系统中各结构对控制系统性能的影响。

净化柱结合超高效液相色谱—串联质谱检测动物源性食品中16种喹诺酮药物

目的:加强动物源性食品安全检测市场监管。方法:动物源性食品样品使用80%乙腈(含0.2%甲酸)提取,净化柱(Speedy Prep-Quino 1)净化后,利用超高效液相色谱—串联质谱检测16种喹诺酮类药物残留。结果:16种喹诺酮类药物的线性范围为1.6~40.0μg/kg,相关系数r≥0.9961,检出限为0.14~0.80μg/kg,定量限为0.47~2.68μg/kg。在净化柱前处理后7个基质加标回收率为62%~112%,相对标准偏差为0.9%~18.7%。结论:该方法具有检测速度快、灵敏度高的特点,适用于羊肉、鸭肉、牛肉、鱼肉、鸡蛋、猪腰、鸭皮等动物源性食品。

加氢提馏塔运行异常分析及优化

煤油加氢精制装置提馏塔经过运行,存在底部nC_(10)损失率高、塔底热油用量高、塔底换热器堵塞等诸多问题。针对问题进行逐一分析,发现精馏塔分离效果下降导致底部nC_(10)损失率高、塔底精制煤油nC_9含量高,塔底换热器都是检修以后初期使用容易发生堵塞,换热器换热效果降低是由于装置波动导致换热器结垢,从而造成换热效率降低。因此逐一采取措施,利用ASPEN PLUS分析、优化提馏塔,在精馏塔塔底至出料换热器之间增加一台篮式过滤器,利用检修机会对部分换热器进行清理,优化精馏塔热负荷。措施实施后,产品收率得到提高,装置能耗降低,塔底堵塞问题得到解决,换热器换热效率得到提高,以达到了节能降耗的目的,相关经验和做法可为同行借鉴。

超深大位移井高效井筒清洁与预校深一体化提效工艺

超深大位移井的井眼轨迹复杂、井斜大、稳斜段长,常规套管程序为ϕ244.5 mm套管与ϕ177.8 mm尾管复合,且刮管洗井阶段存在随钻预校深为射孔备用的需求,常规采用两趟管柱分别实现井筒清洁、随钻预校深的功能,造成井筒清洁效率低、作业周期长。通过集成优化组合多功能清洁工具、可变径刮管器、随钻测井工具和分流转向阀工具,设计形成了高效井筒清洁与预校深一体化管柱结构,重点开展了水力学模拟、管柱安全评价、工艺流程优化,实现复合井筒一趟式高效清洁和随钻预校深一体化功能,相比常规两趟式方案提效30%。该技术在东海3口超深大位移井中成功应用,井下工具工作正常,相比同类井型常规工艺单井平均缩短43.6 h,具有显著的提速提效作用。

The Effect of Water Spray upon Incineration Flue Gas Clean-up

The existence of liquid water was found very important in incineration flue gas clean-up systems for enhancing the absorption of acid components contained. In a newly developed incineration flue gas clean-up tower, which works in a semi-dry mode, the water is injected in the form of spray to maximum its contact surface with the gas. The criteria for the design of the water nozzles would be nigh water concentration but no liquid impinging on the solid wall and complete evaporation inside the tower. In order to optimize the atomizer design, the effects of the spray type (hollow or solid cone), their initial droplet she distribution and water flow rate on the performance of the acid gas absorption were investigated. The liquid behaviour was studied with a fluid dynamic simulation code, and the overall performance was checked experimentally. This paper presents the use of a commercial CFD code, FLUENT, and some modifications made during such investigation. The modification includes the viscosity of the flue gas defined as a function of the temperature, and the initial mass fraction of different droplet size group described with an exponential distribution formula of Rosin-Rammler. The investigation results (the optimal spray parameters) were used to guide the water nozzle design. The general performance of the flue gas clean-up system measured during the plant operation complied with the design criteria.

婴儿配方乳粉中V_(A)、V_(D)和V_(E)混合标准物质的研制

研制婴儿配方乳粉中V_(A)、V_(D)和V_(E)混合标准物质。选择与日常检测水平相当的乳粉,经过混匀、分装、真空密封制备了候选标准物质。采用固相萃取-二维液相色谱建立了一种测定婴儿配方乳粉中V_(A)、V_(D)和V_(E)含量测定的通用方法,并将此法用于该标准物质的均匀性、稳定性检验及定值。定值采用同一检测方法8家实验室协作定值方式,并对标准物质的不确定度进行评估。采用该方法考察标准物质的均匀性和稳定性结果满足标准物质制备的要求。标准物质中V_(A)、V_(D)和V_(E)含量定值结果及其扩展不确定度(k=2)分别为(4987±3.1)μg/kg、(104±1.59)μg/kg和(90±1.3)mg/kg。该研究流程和结果符合标准物质定值的要求。该标准物质可用于相关检测实验分析方法的确认和过程质量控制。

4TWZ-2型甜菜挖掘装运收获机研制与试验

甜菜机械化收获替代人工收获,可有效降低劳动强度,提高甜菜挖掘效率和收获质量。国内现有甜菜收获机型存在着技术性能落后、联合作业能力差及智能化程度低等问题。依据甜菜机械化收获农艺技术要求,在传统甜菜挖掘机的基础上,根据实际需要加装清理夹持链、圆形升运笼及可倾卸料斗等工作部件。阐述了机具整体结构和工作原理,确定了挖掘部件、打缨器、输送分离、集运装卸以及传动系统等关键部件的基本参数。通过田间试验验证了该机作业性能稳定,增加联合作业功能的同时收获效果也显著提升,试验结果满足甜菜收获农艺技术要求。

How do international agreement constraints affect marine litter management strategies?A research based on differential game

Based on differential game theory,the decision-making problem of two homogeneous countries facing transboundary marine litter governance is studied.On the basis of assuming that the input of marine litter is an exogenous variable,the focus is on reducing the accumulation of marine litter through cleanup and transfer processing by both parties.Considering the constant and increasing input of marine litter,in the framework of international agreement constraints,the analysis of the game behavior of the players in the marine litter governance under the open-loop strategy(in the case of agreement constraints)and the Markov strategy(in the case of no agreement constraints)was compared and analyzed.The research results show that when the direct pollution cost of marine litter is high enough,both sides of the game adopt an open-loop strategy that complies with the constraints of the agreement,which can reduce the accumulation of marine litter and improve the environmental quality.However,when there is a high initial accumulation of marine litter,the Markov strategy without protocol constraints will be better than the open-loop strategy.In the case that marine litter does not need to be transferred,there will be no difference between the two sides of the game adopting the Markov strategy and adopting the open-loop strategy on the equilibrium growth path.

高效液相色谱-三重四极杆复合线性离子阱质谱法检测水产品中氟喹诺酮类抗生素和镇静剂

为实现水产品中抗生素和镇静剂的同时、快速检测,进行了题示研究。分取2.0 g匀浆后的样品的肌肉组织,加入体积比79∶1∶20的乙腈-乙酸-水混合溶液10 mL,振荡1 min,超声10 min。加入2.0 g氯化钠,振荡1 min,于-20℃保存30 min,用于去除提取液中的脂肪。离心10 min,分取1 mL上清液注入装载有150 mg C18的CAFS clean-up净化柱中,多次推动活塞,将提取液全部转移到2 mL离心管中。分取0.5 mL净化液,加入0.5 mL 0.1%(体积分数,下同)甲酸溶液,混匀后过0.22μm尼龙滤膜。滤液注入高效液相色谱-三重四极杆复合线性离子阱质谱仪,9种目标物在BEH C18色谱柱上用不同体积比的0.1%甲酸溶液和含0.1%甲酸的甲醇溶液的混合溶液进行梯度洗脱分离后,用电喷雾离子源正离子(ESI+)模式电离,多反应监测(MRM)模式检测,基质匹配法定量。结果显示,9种目标物的质量分数分别在1.0~50.0μg·kg^(-1)(丁卡因、布比卡因、恩诺沙星和氧氟沙星)、2.0~50.0μg·kg^(-1)(地西泮和氟罗沙星)、5.0~50.0μg·kg^(-1)(环丙沙星、培氟沙星和洛美沙星)内与对应的峰面积呈线性关系,检出限为0.2~1.0μg·kg^(-1);对空白草鱼样品进行3个浓度水平的加标回收试验,回收率为99.1%~110%,测定值的相对标准偏差(n=6)分别为1.9%~8.2%(日内精密度试验)和2.6%~8.5%(日间精密度试验)。方法用于28份水产品的分析,检出了1种镇静剂布比卡因(检出量为1.41μg·kg^(-1))以及4种氟喹诺酮类抗生素[洛美沙星、培氟沙星、环丙沙星(3种抗生素检出量均低于测定下限)和恩诺沙星(检出量为2.43~4.61μg·kg^(-1),低于GB 31650-2019规定的限量)]。

甲状腺癌^(131)Ⅰ治疗患者被服清洁解控方案的构建

目的构建^(131)Ⅰ治疗甲状腺癌患者被服清洁解控方案,为临床被服清洁解控的开展提供借鉴。方法通过临床调研、文献研究、影响因素分析、半结构访谈和课题组讨论,构建^(131)Ⅰ治疗甲状腺癌患者被服清洁解控方案初稿。采用德尔菲专家咨询法,选取30名专家进行2轮专家咨询,结合研究小组讨论构建^(131)Ⅰ治疗患者被服清洁解控方案。结果2轮专家咨询问卷回收率均为100%,第2轮咨询中,各条目的变异系数为0.00~0.24,重要性得分为4.13~5.00分,专家权威系数为0.867,一级、二级、三级指标的肯德尔和谐系数分别为0.475、0.420、0.292(均P<0.05),形成的^(131)Ⅰ治疗甲状腺癌患者被服清洁解控方案包括5个一级指标、20个二级指标、59个三级指标。结论^(131)Ⅰ治疗甲状腺癌患者被服清洁解控方案构建过程规范严谨,可为临床^(131)Ⅰ治疗甲状腺癌患者被服的清洁解控提供指引。

多功能净化柱-光化学衍生高效液相色谱法测定成品植物油和花生原油中黄曲霉毒素B1

为了快速、准确测定成品植物油和花生原油中黄曲霉毒素B1(AFB1)的含量,建立了采用多功能净化柱对油样进行前处理,再结合光化学衍生高效液相色谱法测定植物油中AFB1含量的方法,对前处理提取剂、高效液相色谱法的分析条件(色谱柱、进样量)进行优化,再通过与国标中免疫亲和柱法进行比较,对所建立的方法进行评价。结果表明:优化的条件为以乙腈-水溶液(84+16)为提取剂,采用Zorbax Eclipse XDB-C18色谱柱(4.6 mm×150 mm,5μm),进样量10μL;建立的方法加标回收率和精密度良好,定量限为0.2μg/kg,低于GB 2761—2017规定的最低限量值要求,可满足企业生产的监测需求;将建立的方法用于测定浅色植物油中AFB1时,检测结果与免疫亲和柱法相比相对误差为0~18.0%,符合国标要求,但对于深色植物油测定的相对误差超出国标要求。综上,建立的方法可用于快速、准确检测花生油(成品油和原油)及成品玉米油、亚麻籽油、葵花籽油、浅黄色菜籽油、黄色芝麻油中AFB1的含量。