垃圾问题的思考

垃圾在告急：垃圾的恶性累积,已成为世界性的环境灾难。对垃圾问题的哲学思考：垃圾是与人类社会同时产生,同步发展的。根据事物发展否定之否定规律,垃圾危机的产生正是对已往社会发展的一种否定。解决垃圾问题,必需树立社会全面发展观和科技全面进步观,运用法律的、经济的、行政的和道德的手段,大力发展处理垃圾的科学技术,减少垃圾的产生,并将产生的垃圾“变废为宝”,才能使社会在否定之否定的过程中持续发展。     

我国城市生活垃圾的处理和发展趋势

城市生活垃圾给城市环境造成了严重污染，威胁了城市居民的生存环境和经济、社会的可持续发展。目前，国内采取的垃圾处理技术主要有卫生填埋、焚烧、堆肥等，热解技术由于具有资源回收率高、二次污染小、综合效益好等优点，越来越适合我国中小城市的垃圾处理。垃圾气化技术的研究成为当今世界的热点。此外，我国对垃圾衍生燃料的研究也刚刚起步。为促进城市持续、稳定的发展，提出了垃圾分类收集、分拣、综合利用垃圾处理技术的措施。     

WATER RESOURCES AND HUMAN HEALTH: THE VIEWPOINT OF MEDICAL GEOGRAPHY1

ABSTRACT: Medical geography studies both areal patterns of human health and disease and the environmental and cultural factors that contribute to such conditions. In such studies water resources are of major importance, not only because they are essential for life and their scenic beauty is of inspirational value, but also because they are involved, directly or indirectly, in more than 80 percent of all disease. The direct involvements result from various disease causing agents sometimes found in surface or ground water organic ones such as bacteria, worms, etc., which are known as pathogens, and inorganic ones such as trace elements and synthetic toxic chemicals. Surface waters may have indirect effects also, for they may serve as habitats or breeding places for organisms that do not themselves cause human disease but that serve as vectors or hosts for such pathogens. This paper will discuss these various roles of water resources in both endemic and epidemic disease occurrences and ways in which various human activities domestic, economic, recreational, or religious — increase or reduce our exposure to such diseases.     

基于粒子群算法的城市垃圾中转站的空间布局研究

随着城市化的进程，垃圾处理设施成为影响城市化质量的重要指标。依据人们实际所关注的垃圾处理设施的总成本和负效应两个因素，在前人研究的基础上，建立了垃圾收运多目标模型，使得总成本和负效应最优化。根据模型设计了粒子群算法，该算法属于智能算法，且精度高，收敛快，在许多领域也得到广泛应用。用设计的粒子群算法并结合案例求出了Pareto最优解，给出三种决策方案，验证了模型和算法的有效性和可行性，为决策者提供了一种理论参考。     

医疗废物制备木酢液及其成分分析

为了解以医疗废物为原料的木酢液制备特性和木酢液的成分,采用磁化热解装置进行调制试验,收集了热解冷凝液,并采用GC-MS对冷凝液的成分进行了分析。检测出有机酸、酚、醛、酮、酯等38种有机成分,并采用面积归一化法对主要成分进行定量分析。结果表明,医疗废物磁化热解冷凝液中的成分种类与木酢液十分接近,特别是乙酸(18.48%)与苯酚(5.15%)的含量较高,证明了依靠磁化空气热解医疗废物制备木酢液的可行性。而两者之间存在的成分差异对其功用的影响则有待进一步探究。     

医疗废物处置厂污水处理技术

从污水处理工艺、处理方式、水量平衡和自动控制方面论述了医疗废物处置厂污水处理系统,并申请了发明专利。根据医疗废物处置厂水质复杂、水量小、需中水回用等特点,采用物化、生化和微滤膜处理工艺,达到中水回用标准。消毒废水单独处理,循环使用。     

医疗废物焚烧厂周边环境空气中二英浓度分布及其健康风险评估

于2015-2018年冬季（12月-2月）对广东省某医疗废物焚烧厂排放烟气及焚烧设施周边2.5 km范围内6个采样点分别进行了4次烟气和环境空气样品采集,应用高分辨气相色谱/高分辨质谱（HRGC-HRMS）联用技术对二（口恶）英（PCDD/Fs）浓度水平进行监测并对其组成特征进行了分析,运用主成分分析法（PCA）对周边环境空气中二（口恶）英来源进行了初步解析,同时采用VLIER-HUMAAN模型评估其对人体的健康风险.结果表明该医疗废物焚烧厂烟气二（口恶）英毒性当量浓度为0.542~21.300 ng·Nm^-3（以I-TEQ计）,排放水平较高;周边环境空气中PCDD/Fs质量浓度和毒性当量浓度变化范围分别为0.682~196.000 pg·m^-3和0.036~17.700 pg·m^-3（以I-TEQ计）,周边环境空气中PCDD/Fs浓度明显受到排放源烟气落地点的影响.空气样品中二（口恶）英同族体及异构体分布指纹谱图与该焚烧设施排放烟气类似,空气质量浓度主要贡献单体以OCDD、1,2,3,4,6,7,8-HpCDF、OCDF以及1,2,3,4,6,7,8-HpCDD为主,主要毒性贡献单体为2,3,4,7,8-PeCDF.PCA源解析结论与指纹谱图特征分析结论基本一致,该研究区域中环境空气二（口恶）英主要来源于医疗废物焚烧烟气排放.健康风险评估结果表明,该区域人群呼吸暴露风险总体处于较为安全的水平（0.0032~0.141 pg TEQ·kg^-1·d^-1）,部分个体的呼吸暴露贡献率超过了评价限值,应引起重视.     

基于我国人群胃肠消化特征的土壤中As的人体可给性研究

基于我国人群胃肠消化特征,采用医学配方模拟胃肠消化方法测试了来自大连、湖南和广西的13个受重金属污染土壤中As的人体可给性,分析了土壤理化参数与可给性的相关关系及提取液中酶、胃肠液pH值、提取时间对As的人体可给性的影响.结果表明,医学配方可给性测试中,供试土样在胃、肠阶段As的人体可给性分别为5.03%~44.54%和10.77%~51.46%,平均值为18.08%、29.32%.胃阶段As的可给性浓度与土壤中总As含量w（TAs）、总P含量w（TP）极显著正相关,与总Al含量w（TAl）、土壤pH值、总有机质含量w（TOM）显著相关;肠阶段As的可给性浓度与土壤中w（TAs）、胃阶段As的可给性浓度、w（TP）极显著相关,与土壤pH值、w（TAl）和w（TOM）显著相关.胃阶段提取液中的胃蛋白酶显著降低了As的可给性,而肠阶段添加胰蛋白酶As的可给性没有明显变化.胃、肠阶段分别在pH值为0.9和5.0时可给性最大,0.9和5.0可分别作为土壤As在可给性测试过程中模拟胃肠液的pH值.胃、肠阶段在提取时间分别为1.0h、4.0h时可给性达到最大,且之后基本不变,1.0h、4.0h可作为模拟测试As在胃肠中可给性的提取时间.研究结果表明开展基于我国人群胃肠消化特征的土壤重金属人体可给性测试方法具有重要意义.     

Seat belt use in the ambulance patient compartment by emergency medical services professionals is low regardless of patient presence,seating position,or patient acuity

Background: Inconsistent use of seat belts in an ambulance may increase the risk of injury for emergency medical services (EMS) professionals and their patients. Our objectives were to: (1) describe the prevalence of seat belt usage based on patient acuity and seat location, and (2) assess the association between EMS-related characteristics and consistent use of a seat belt. Methods: We administered a cross-sectional electronic questionnaire to a random sample of 20,000 nationally-certified EMS professionals, measuring seat belt use in each seating location of an ambulance during transport of stable, critical, or no patients. We included practicing, non-military, emergency medical technicians or higher who reported working in ambulances. We used multivariable logistic regression models to estimate the odds of consistent (≥50% of the time) use of seat belts for the rear-facing jump seat and right-sided crew bench during transport of stable and critical patients. Results: A total of 1431 respondents were included in the analysis. Patient compartment seat belt use varied with the highest use in forward-facing seats when no patient was being transported (59.8%) and lowest use in the left-side “CPR” seat with a critical patient (9.4%). Only 40.2% of respondents reported an agency policy regarding seat belt use while riding in the patient compartment. In all multivariable logistic regression models, advanced life support level certification and fewer years of experience were associated with decreased odds of consistent seat belt use. An agency seat belt policy was strongly associated with increased odds of seat belt use in the patient compartment. Conclusions: Seat belt use was low and varied by seating location and patient acuity in the patient compartment of an ambulance. Practical Applications: EMS organizations should consider primary prevention approaches of provider education, improved ambulance designs, enactment and enforcement of policies to improve seat belt compliance and provider safety.     

Radiation hormesis — fact or fiction?

Deriving from the Greek verbhormein, which means to stimulate and excite, hormesis literally refers to any kind of stimulation and excitation. As a medical and geomedical term (though of unsettled status) it has a more restricted meaning however, indicating merely the putative or real stimulatory and beneficial effects observed when a biological system is exposed to a low dose of an agent known to be toxic or hazardous at a significantly larger dose. Depending on the type of stimulatory agent, one can speak of chemical or physical hormesis, radiation hormesis being a member of the latter group. The present paper reviews and evaluates the history and origins of the concept of radiation hormesis and its present status — fact or fiction. It is concluded that despite the numerous, sometimes undeniably strong, individual pieces of evidence that have been presented in favour of this phenomenon, the bulk of the evidence is so far not strong enough to establish it as a scientifically proven fact. It is also evident that, instead of speaking of radiation hormesis as an entity, one should pay attention separately to the effects of alpha, beta and gamma radiation, the deleterious and possible beneficial hormetic effects being different in each case.