Release of Uranium by an Ore Treatment Unit at Caldas,MG,Brazil

This study aims to assess the behavior of the release of Unat (i.e. uranium isotopes in natural relative abundance) from the release of water treated by the Ore Treatment Unit (UTM) in Caldas, state of Minas Gerais, Brazil, during the years 1999 to 2009. During this period, the unit showed no industrial activity, except between 2004 and 2005, when UTM operated 400 tons of monazite in a process to obtain rare earths. Unat was analyzed by spectrophotometry once per week in the effluent waters at sampling point 014. Two fractions were considered for analysis: the soluble one (that passes through a 0.45 μm filter) and the particulate one (retained on a 0.45 μm filter). Statistical analyses were performed: the “Z” test and Pearson’s r2 correlation index. The values for the soluble fraction were consistently lower than those of the particulate fraction and no statistically significant correlation was observed between the soluble and particulate fractions. However, the particulate and the total fractions (the sum of soluble and particulate) strongly correlated.

Delayed Grafting as a Valid Technique in Burn Management: Experience from a Burn Unit in Oman

Background: Early excision and grafting has been the preferred method of managing major burns around the world since 1970. Considering the advances in health care and the development of new antibiotics over the past 50 years, delayed grafting as a technique for the management of burns over 15%-20% of total body surface area (TBSA) could have comparable results to that of early excision. This study aims to highlight the outcomes of practicing delayed grafting in burn patients. Methods: A case series analysis was performed of 51 patients who were admitted to the burns unit in Sultan Qaboos Hospital Salalah with over 20% TBSA between January 2014 and December 2019. The patients received prophylactic antibiotics and silver sulphadiazine dressing until the burn eschar had completely separated, followed by grafting. Results: Two patients were lost during the entire duration of the study. The mortality rate was comparable to that of early excision, while the rate of hypertrophic scarring was lower than the range reported by other studies. Conclusion: In the management of patients with over 20% TBSA, delayed grafting after complete separation of eschar is still a valid technique.

Performance Simulation of H-TDS Unit of Fajr Industrial Wastewater Treatment Plant Using a Combination of Neural Network and Principal Component Analysis

Nowadays, with regard to environmental issues, proper operation of wastewater treatment plants is of particular importance that in the case of inappropriate utilization, they will cause serious problems. Processes that exist in environmental systems and environmental engineers are dealing with them mostly have two major characteristics: they are dependent on many variables;and there are complex relationships between its components which make them very difficult to analyze. Being familiar with characteristics of industrial town effluents from various wastewater treatment units, which have high qualitative and quantitative variations and more uncertainties compared to urban wastewaters, plays very effective role in governing them. In order to achieve a better and efficient control over the operation of an industrial wastewater treatment plant, powerful mathematical tool can be used that is based on recorded data from some basic parameters of wastewater during a period of treatment plant operation. In this study, the multilayer perceptron (MLP) feed forward neural network with a hidden layer and stop training method was used to predict quality parameters of the industrial effluent. Data of this study are related to the Fajr Industrial Wastewater Treatment Plant located in Mahshahr—Iran that qualitative and quantitative characteristics of its units were used for training, calibration and evaluation of the neural model. Also, Principal Component Analysis technique was applied to modify and improve performance of generated models of neural networks. The results of this model showed good accuracy of the model in estimating qualitative pro- file of wastewater. This model facilitates evaluating the performance of each treatment plant units through comparing the results of prediction model with the standard amount of output.

Hg-CEMS烟气预处理关键问题研究与进展

鉴于汞在化石燃料和矿物资源中的天然禀赋以及能源与资源利用过程中汞污染物的排放与监管,研发我国自主知识产权的汞连续在线监测系统(Hg-CEMS)成为汞排放浓度监测的国家重大需求。烟气预处理技术是Hg-CEMS系统中最关键的组成部分,也是限制我国Hg-CEMS技术发展与应用的核心技术。对Hg-CEMS烟气预处理技术中的4个关键模块——稀释采样模块、Hg0/Hg^(2+)分离模块、Hg^(2+)还原模块、Hg^(2+)标气发生模块的研究进展进行全面综述。首先,介绍稀释采样技术的原理与应用,阐述音速小孔和热稀释引射器的结构和设计要点,论述数值模拟与优化设计相结合的方法。其次,针对Hg0/Hg^(2+)分离技术,综述湿法吸收、物理吸附和化学吸附的研究新进展,讨论选择性吸附剂KCl和CaO的理论和实验研究结果。第3,针对Hg^(2+)还原技术,概述湿化学还原、低温还原和高温分解还原的技术,论证低温还原技术中固态还原剂的活性成分、反应温度以及烟气成分对氧化态汞还原的影响,探讨高温分解还原技术中填充材料、酸性气体组分以及除酸剂对Hg^(2+)还原和抑制Hg0再氧化的新研究进展。最后,针对Hg^(2+)标气发生技术面临的技术难点,提出固态标气发生新技术理念并指出其工业应用的可行性。结合当前Hg-CEMS技术的研究发展和应用现状,提出上述4个关键模块的研究思路、解决方案与应用前景。

Method for Converting Cone-Beam CT Values into Hounsfield Units for Radiation Treatment Planning

Cone-beam CT (CBCT) images acquired during radiation treatment can be used to recalculate the dose distribution as well as to confirm the treatment location. However, it is difficult to obtain the electron densities (EDs) necessary for dose calculation from CBCT images because of the effects of scatter contamination during CBCT image acquisition. This paper presents a mathematical method for converting the pixel values of CBCT images (CBCT values) into Hounsfield units (HUs) of radiation treatment simulation CT (simCT) images for use in radiation treatment planning. CBCT values are converted into HUs by matching the histograms of the CBCT values with the histograms of the HUs for each slice via linear scaling of the CBCT values. For prostate cancer and head-and-neck cancer patients, the EDs obtained from converted CBCT values (mCBCT values) show good agreement with the EDs obtained from HUs, within approximately 3.0%, and the dose calculated on the basis of CBCT images shows good agreement with the dose calculated on the basis of the simCT images, within approximately 2.0%. Because the CBCT values are converted for each slice, this conversion method can account for variation in the CBCT values associated with differences in body size, body shape, and inner tissue structures, as well as in longitudinally displaced positions from the isocenter, unlike conventional methods that use electron density phantoms. This method improves on conventional CBCT-ED conversion and shows considerable potential for improving the accuracy of radiation treatment planning using CBCT images.

某大型综合医院神经外科重症监护患者营养治疗实施状况分析

目的:分析南通大学附属医院神经外科重症监护病房(neurosurgery intensive care unit,NICU)收治患者的营养治疗现状。方法:以2022年1月—2023年1月入住南通大学附属医院NICU的患者为调查对象,收集患者基本信息和临床指标,包括营养风险筛查评分(nutrition risk score 2002,NRS 2002)、危重症营养风险评分(nutrition risk score in the critically ill,NUTRIC)、胃肠功能损伤分级、营养治疗实施的时机和途径、入病房第1、3和7天热卡及蛋白达标情况、喂养耐受情况以及患者的28 d临床转归情况。结果:调查共收集患者133例,平均年龄(58.3±15.4)岁。患者格拉斯哥昏迷评分、序贯器官衰竭评分和急性生理与慢性健康评分分别为(4.07±2.41)、(7.10±2.59)、(11.0±3.4)分。28 d临床转归存活100例(75.2%),死亡33例(14.8%)。除BMI(P=0.0192)外,男性与女性患者在年龄、病情严重程度方面差异均无统计学意义(均P>0.05)。133例患者中,胃肠功能正常或轻度损害95例(71.4%),中-重度损害29例(21.8%),衰竭8例(6.0%)。入NICU 24 h内即开始肠内营养(enteral nutrition,EN)患者82例(61.7%)。72 h内达到20 kcal/(kg·d)的热卡目标的有28例(31.5%),1周总热卡达标率为12.3%(11/89),达到80%蛋白质喂养目标的有5例(3.76%)。高营养风险组的白蛋白水平在入NICU第7天显著低于低营养风险组。结论:目前我院NICU内超过70%的患者在48 h内接受EN治疗,喂养期间出现最多的不耐受症状是腹胀。补充性肠外营养的比例、1周左右的热卡及蛋白达标率均较低。应加强个性化制定热卡和蛋白目标进行营养补充。

镇痛镇静治疗对神经外科重症监护室患者颅内压及预后的影响研究

研究了镇痛镇静治疗对神经外科重症监护室(neurosurgical intensive care unit,NICU)患者颅内压及预后的影响。以接受不同治疗方法的NICU外伤性高颅压患者为例,比较了观察组和对照组患者的镇痛镇静效果、颅内压、意识状态、神经功能以及预后情况。结果表明,观察组VAS评分、Ramsay评分、颅内压、NIHSS评分均低于对照组,GCS评分均高于对照组,预后情况的有效率高于对照组,P<0.05。由此可见,联合应用镇痛镇静治疗对于神经重症监护室的患者是有效的,能降低患者的颅内压,减轻昏迷程度,改善NICU患者的神经功能,对患者康复预后有积极影响。

Simulation of Low TDS and Biological Units of Fajr Industrial Wastewater Treatment Plant Using Artificial Neural Network and Principal Component Analysis Hybrid Method

Being familiar with characteristics of industrial town effluents from various wastewater treatment units, which have high qualitative and quantitative variations and more uncertainties compared to urban wastewaters, plays very effective role in governing them. With regard to environmental issues, proper operation of wastewater treatment plants is of par- ticular importance that in the case of inappropriate utilization, they will cause serious problems. Processes that exist in environmental systems mostly have two major characteristics: they are dependent on many variables;and there are complex relationships between its components which make them very difficult to analyze. In order to achieve a better and efficient control over the operation of an industrial wastewater treatment plant (WWTP), powerful mathematical tool can be used that is based on recorded data from some basic parameters of wastewater during a period of treatment plant operation. In this study, the treatment plant was divided into two main subsystems including: Low TDS (Total Dissolved Solids) treatment unit and Biological unit (extended aeration). The multilayer perceptron feed forward neural network with a hidden layer and stop training method was used to predict quality parameters of the industrial effluent. Data of this study are related to the Fajr Industrial Wastewater Treatment Plant, located in Mahshahr—Iran that qualita- tive and quantitative characteristics of its units were used for training, calibration and validation of the neural model. Also, Principal Component Analysis (PCA) technique was applied to improve performance of generated models of neural networks. The results of L-TDS unit showed good accuracy of the models in estimating qualitative profile of wastewater but results of biological unit did not have sufficient accuracy to being used. This model facilitates evaluating the performance of each treatment plant units through comparing the results of prediction model with the standard amount of outputs.

天然气净化厂文丘里组合式急冷塔流场模拟与优化

康索夫尾气处理装置应用于天然气净化厂处理高温含硫烟气时,文丘里组合式急冷塔文丘里段(以下简称文丘里段)设备内部喷淋水线上方约30 cm处出现环状腐蚀环。针对设备腐蚀问题,利用计算流体力学软件模拟文丘里段气液流体流动及传热传质过程,研究腐蚀机理并提出优化方案。设备腐蚀原因是高温含硫烟气中的酸性组分被喷淋冷却时,与水蒸汽反应产生硫酸,当气体温度降至酸露点以下时产生高浓度硫酸,致使254SMo合金钢设备内壁发生严重酸腐蚀。文丘里段内部腐蚀无法完全解决,经模拟计算,改变喷淋雾化效果及喷嘴的喷淋夹角可大幅改变气液界面位置,改善设备腐蚀情况。研究成果可为类似文丘里组合式急冷塔在设计及运维方面提供参考。

典型污水处理工艺各工序全氟化合物赋存及去除效果

全氟化合物(PFAS)是我国重点管控的新污染物,污水处理厂是其进入水体的重要节点,当前污水处理厂的工艺多为提标改造后的综合工艺,各工艺去除PFAS的效果不一。为探究当前不同污水处理工艺对PFAS去除效果的影响,对北京市某污水处理厂的2种典型污水处理工艺(改进型A^(2)O、改进型OD)各工序的PFAS浓度和组分特征进行了分析,并探讨PFAS去除机制。结果表明:1)该污水处理厂纳管范围内短链替代效应已经显现,2种典型污水处理工艺进水中主要PFAS均为短链PFAS的全氟戊烷羧酸(PFPeA)、全氟丁烷羧酸(PFBA)和全氟丁烷磺酸(PFBS);2)生化处理单元、紫外消毒池导致的PFAS前体物分解,格栅、MBR池、沉淀池等对PFAS的拦截滤除、吸附及沉淀作用是2种典型污水处理工艺中PFAS赋存特征变化的重要机制;3)改进型A^(2)O、改进型OD工艺对总PFAS的去除率分别为60.65%、82.62%,前者对PFPeA和PFBS去除效果突出,后者对除全氟己烷羧酸(PFHxA)以外的所有短链PFAS均有较好的去除效果。污水处理工艺提标改造后在一定程度上对部分PFAS的去除效果有所提高,尤其是改进型OD工艺对PFAS的去除效果较好。

专科医联体核心单位建设困境探析及策略建议

医联体是深化医疗卫生体制改革、有效配置医疗卫生资源、提高医疗服务效能的有效途径和重要举措,目的是通过有效整合区域内医疗卫生资源,进一步落实分级诊疗,提升医联体内医疗机构整体的卫生服务能力。跨区域专科医联体是医联体中一种重要补位发展模式,是根据区域内医疗机构优势专科资源,以一所医疗机构特色专科为主,联合其他医疗机构相同专科技术力量,形成区域内若干特色专科中心,在提升解决专科重大疾病的救治能力,推动专科医疗资源共享中发挥着至关重要的作用。因专科联盟大部分为松散型运转模式,作为跨区域专科医联体的牵头核心建设单位在专科医联体发展和建设中起着至关重要的作用,是带动区域专科发展的领头羊。本文通过实例“福州儿科医疗联合体”建设过程研究,结合区域内医疗卫生事业的实际发展情况,深入探析医联体的核心单位在建设中面临的困境,并提出可行性的策略建议,为各地推进专科医联体发展提供思路借鉴。

外科ICU谵妄评估及治疗研究进展

近年来,随着外科手术技术不断完善、成熟和人类疾病谱的变迁,我国外科手术的需求量不断增长,外科手术的安全性引起了临床医师的广泛关注。尽管目前外科技术已日趋完善,但作为一种创伤性治疗手段,其术后并发症并不少见。谵妄是外科术后最常见的神经系统并发症,以意识、注意障碍、认知功能改变等为主要表现,多为急性发作,病情易反复波动。而谵妄的发生不仅会增加外科重症监护室(ICU)患者并发症的发生风险,延长机械通气和ICU住院时间,增加患者个人和社会的经济负担,还可能对患者的远期脑功能产生负面影响。早期诊断和治疗是改善患者预后的关键。现就外科ICU患者谵妄的发生机制、临床分型、评估工具和治疗现状进行综述,以期为外科ICU患者谵妄的诊断和干预提供参考。

污水处理装置排放超标控制措施研究

针对目标污水处理装置采用加药絮凝的方式对污水进行处理,出现了出口系统水质污染物排放超标的现象,在分析进水系统和出水系统水样水质指标的基础上,考察了不同类型絮凝剂对污水处理效果的影响,优选出性能较好的复合絮凝剂FX-1,并考察了污水处理装置的长时间运行效果。结果表明:FX-1的使用能够有效降低目标污水处理装置出口端水样中的各项污染物浓度,且出水系统水样各项污染物浓度在12个月内均能得到有效控制,COD、悬浮物、氨氮、总氮、总磷和石油类含量均能达到GB 18918—2002中“一级A标准”要求,实现了目标污水处理装置高效稳定运行。

炼油厂加氢装置设备的防腐措施研究

炼油厂加氢装置作为辅助炼油的关键设备,直接影响炼油的质量以及效率。加氢装置设备会受到诸多因素的影响出现腐蚀状况,对设备造成损坏,所以常规防腐蚀材料难以适应整体耐腐蚀的管理要求,对腐蚀防护提出了更高要求,文章对加氢装置设备的防腐措施进行了分析探讨。

医疗卫生用非织造布制品碳足迹核算关键问题探究

为系统分析医疗卫生用非织造布制品碳足迹核算的关键问题,对医疗卫生用非织造布制品碳足迹的研究文献进行总结与分析,并对生产阶段的耗电量数据拆分、废弃阶段的碳减排措施及制品功能单位设定等医疗卫生用非织造布制品碳足迹核算的关键问题进行探讨。

硅钢热处理机组活套抖动抑制

在对硅钢老旧热处理机组产能、运行速度进行相应提升的过程中,由于大部分机组远超原有设计速度上限,对活套的稳定性影响较大,导致活套内的带钢出现了明显的张力、速度的抖动。通过分析活套间接张力控制的原理,根据前馈原理设计了活套抖动抑制器,有效抑制了活套抖动问题,并推广到同类机组,效果明显。

抽油机偏磨原因及治理措施

伴随经济社会的进步,石油开采业进入全新的历史发展阶段,抽油机在油田开采中扮演着关键角色,关系到石油开采的效率与质量。在长期高负荷运转后,受到井身结构限制、管柱失稳弯曲等因素的影响,会造成不同程度的杆管偏磨,不仅会影响后续生产工作的推进,也会增加生产中的风险因素,推进偏磨原因分析及治理显得尤为重要。结合某区抽油机的日常使用,针对偏磨原因及治理措施展开研究,旨在缓解抽油机偏磨问题,保障生产工作的稳步推进。

水电站大坝混凝土施工及裂缝防渗处理研究

在开展水电站大坝施工阶段,缺乏对混凝土工程的系统化研究,导致透水率难以达到施工要求,基于此,提出水电站大坝混凝土施工及裂缝防渗处理施工技术研究。将普通硅酸盐水泥P·O42.5作为主要材料,从性能角度出发,对大坝混凝土施工材料进行设计,采用多个单元墙段逐个施工的方式对大坝结构浇筑。对于大坝混凝土结构存在的裂缝问题,结合裂缝的具体状态设计了结构表面修补法和内部填充法两种防渗处理施工方式。从测试结果可以看出,施工大坝的透水率始终稳定在1.50 Lu以内,达到了施工管理要求。

硅太阳能电池板生产含氟废水处理工艺研究

文章主要研究了硅太阳能电池板生产中的含氟废水处理工艺,包括某实际含氟废水处理项目的基本情况、含氟废水处理工艺设计分析、含氟废水处理工艺项目投资与运行情况。希望通过本次分析,可以为硅太阳能电池板生产工艺中的含氟废水处理提供一定参考,以此来满足此类废水的实际处理与排放需求。