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Quantificational Study on Carrying Capacity of the Regional Environment-Taking the City of Dalian as an Example

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Ecological Economy 2005年第3期1卷 49-52页

作者： Di Qianbin Cao ke han Zenglin The Research Center of the Marine Economy and Sustainable Development Liaoning Normal UniversityDalian 116029P.R.China. National Marine Envtronment Monitoring Center Dalian 116023P.R.China.

With the analysis of the connotation and charter of the regional environment＇s carrying capacity, this paper, firstly, establishes the index system on the base of the affecting factors. Secondly, this paper discusses the methods of the quantization of the environment＇s carrying capacity of Dalian. Finaly; this paper predicts the changing tendency of the environment＇s carrying capacity.

关键词： environment's carrying capacity index system measure Dalian

基于重症喂养流程的早期肠内营养管理在慢性阻塞性肺疾病急性加重机械通气患者中的应用价值

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中国实用护理杂志 2024年第5期40卷 344-349页

作者：韩婷佘会六安市中医院呼吸内科一科六安237000 六安市中医院护理部六安237000

目的探究基于重症喂养流程的早期肠内营养(EEN)管理对慢性阻塞性肺疾病急性加重(AECOPD)机械通气患者营养状态、胃肠道耐受性的影响。方法采用类实验研究方法, 按照入院时间先后顺序分组, 选择六安市中医院2020年1月至2021年6月住院治疗... 详细信息

目的探究基于重症喂养流程的早期肠内营养(EEN)管理对慢性阻塞性肺疾病急性加重(AECOPD)机械通气患者营养状态、胃肠道耐受性的影响。方法采用类实验研究方法, 按照入院时间先后顺序分组, 选择六安市中医院2020年1月至2021年6月住院治疗的AECOPD机械通气患者30例为对照组, 选择2021年7月至2022年12月的AECOPD机械通气患者30例为观察组。对照组采用常规EEN干预方法, 观察组采用基于重症喂养流程的EEN管理干预方法。比较干预后2组患者7 d内热量摄入量及蛋白摄入量, 记录患者胃肠道耐受情况及预后情况, 比较2组患者干预前及干预第7天的血红蛋白、白蛋白、前白蛋白水平。结果对照组男17例, 女13例, 年龄(66.37 ± 6.09)岁;观察组男16例, 女14例, 年龄(65.49 ± 6.35)岁。干预后, 观察组患者7 d内热量摄入量及蛋白摄入量分别为(3 513.62 ± 94.56)kJ/d、(51.06 ± 5.03)g/d, 均高于对照组的(2 859.41 ± 87.23)kJ/d、(36.78 ± 3.14)g/d, 差异均有统计学意义(t=27.85、13.19, 均P0.05);干预后观察组的白蛋白、血红蛋白、前白蛋白水平分别为(37.16 ± 3.42)、(135.43 ± 12.64)g/L和(218.54 ± 15.38)mg/L, 均高于对照组的(34.25 ± 4.01)、(127.51 ± 11.12)g/L和(201.33 ± 15.04)mg/L, 差异均有统计学意义(t=3.02、2.58、4.38, 均P<0.05);观察组的反流误吸、肠营养中断率均为6.67%(2/30), 低于对照组的26.67%(8/30)和30.00%(9/30), 差异均有统计学意义(χ^(2)=4.32、5.46, 均P<0.05);观察组的机械通气时间、ICU入住时间分别为(7.62 ± 1.35)、(11.17 ± 2.04)d, 均短于对照组的(8.57 ± 1.01)、(12.83 ± 2.19)d, 差异均有统计学意义(t=3.09、3.04, 均P<0.05)。结论基于重症喂养流程的EEN管理干预能够改善AECOPD机械通气患者的营养状态, 提高其胃肠道耐受情况, 改善预后。

关键词：肺疾病慢性阻塞性急性加重期早期肠内营养重症喂养流程营养状态胃肠道耐受性

Inhibition and recovery of nitrification in treating real coal gasification wastewater with moving bed biofilm reactor

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Journal of Environmental Sciences 2011年第4期23卷 568-574页

作者： Huiqiang li Hongjun han Maoan Du Wei Wang State key Laboratory of Urban Water Resources and Environment Harbin Institute of Technology Harbin 150090 China.

Moving bed biofilm reactor （MBBR） was used to treat real coal gasification wastewater. Nitrification of the MBBR was inhibited almost completely during start-up period. Sudden increase of influent total NH 3 concentration was the main factor inducing nitrification inhibition. Increasing DO concentration in the bulk liquid （from 2 to 3 mg/L） had little effect on nitrification recovery. Nitrification of the MBBR recovered partially by the addition of nitrifying sludge into the reactor and almost ceased within 5 days. Nitrification ratio of the MBBR achieved 65% within 12 days by increasing dilute ratio of the influent wastewater with tap water. The ratio of nitrification decreased to 25% when influent COD concentration increased from 650 to 1000 mg/L after nitrification recovery and recovered 70% for another 4 days.

关键词： moving bed biofilm reactor coal gasification wastewater nitrification inhibition nitrification recovery

CA125、CEA、CYFRA21-1、CA19-9、SCC-Ag对肺腺癌的诊断价值及术后复发的预测价值

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中国医师杂志 2024年第2期26卷 228-233页

作者：韩锦胜杨斌河北省沧州中西医结合医院综合外科沧州061000

目的探讨血清肿瘤标志物检测对肺腺癌的诊断价值及术后复发的预测价值。方法选取2018年12月至2020年12月河北省沧州中西医结合医院收治的100例肺腺癌患者(建模组)和100例肺部良性疾病患者(对照组)作为研究对象,另选取2016年12月至2017... 详细信息

目的探讨血清肿瘤标志物检测对肺腺癌的诊断价值及术后复发的预测价值。方法选取2018年12月至2020年12月河北省沧州中西医结合医院收治的100例肺腺癌患者(建模组)和100例肺部良性疾病患者(对照组)作为研究对象,另选取2016年12月至2017年12月收治的50例肺腺癌患者作为验证组,比较建模组和对照组患者血清糖类抗原125(CA125)、癌胚抗原(CEA)、细胞角蛋白21片段(CYFRA21-1)、糖类抗原19-9(CA19-9)和鳞状上皮细胞癌抗原(SCC-Ag)水平,采用受试者工作特征(ROC)曲线评估CA125、CEA、CYFRA21-1、CA19-9、SCC-Ag单独及联合检测对肺腺癌的诊断价值;单、多因素分析影响肺腺癌患者术后复发的危险因素;采用R软件构建预测肺腺癌患者术后复发的列线图模型,并构建危险分层系统。结果建模组患者CA125、SCC-Ag、CEA、CYFRA21-1、CA19-9水平均明显高于对照组(均P<0.05)。ROC曲线显示CA125、CEA、CYFRA21-1、CA19-9、SCC-Ag联合检测对肺腺癌具有较高的诊断价值,其曲线下面积(AUC)为0.903(95%CI:0.865~0.954);CEA、CA125、CA19-9、CYFRA21-1水平升高是影响肺腺癌患者术后复发的独立危险因素(均P<0.05)。通过危险分层将患者分为极低风险组(总分<56分)、低风险组(56分≤总分<132分)、中风险组(132分≤总分<186分)和高风险组(总分≥186分),生存曲线结果表明,不同危险分层系统患者术后复发率间差异有统计学意义(P<0.05)。结论CA125、CEA、CYFRA21-1、CA19-9、SCC-Ag联合检测对肺腺癌具有较高的诊断价值,其中CA125、CEA、CYFRA21-1、CA19-9对患者术后复发具有一定的预测价值。

关键词：肺腺癌复发生物标记,肿瘤列线图

基于PMF 模型和地理探测器的土壤重金属源解析及影响因素分析

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环境科学 2024年第9期45卷 5474-5484页

作者：孙思静董春雨张好杨海婵黄祖志韩宇张乃明包立云南农业大学资源与环境学院昆明650000 云南省土壤培肥与污染修复工程研究中心昆明650000 云南农业大学水利学院昆明650000

以丽江市为例,在研究区内采集93个土壤样品,测定土壤pH、有机质、重金属砷(As)、汞(Hg)、铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)和铬(Cr).通过正定矩阵因子分解(PMF)模型探讨研究区内的重金属来源,将7种重金属与13个影响因子结合地理探测器分... 详细信息

以丽江市为例,在研究区内采集93个土壤样品,测定土壤pH、有机质、重金属砷(As)、汞(Hg)、铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)和铬(Cr).通过正定矩阵因子分解(PMF)模型探讨研究区内的重金属来源,将7种重金属与13个影响因子结合地理探测器分析影响因素的影响力.结果表明,研究区内的土壤重金属ω(As)、ω(Hg)、ω(Cu)、ω(Zn)、ω(Pb)、ω(Cd)和ω(Cr)的均值分别为17.55、0.19、86.75、164.84、28.95、0.39和167.87 mg·kg^(−1),除As和Pb外均超过云南省土壤背景值;在空间分布上,Cu和Cr的含量高值主要集中在玉龙纳西族自治县,As、Hg、Pb和Cd的高值区主要在宁蒗彝族自治县,Zn含量高值主要集中于华坪县;通过相关性分析和PMF模型发现研究区内重金属As和Hg的主要来源是工业源,Zn的主要来源是交通污染源,Cr和Cu的主要来源是自然源,Cd和Pb的主要来源是农业源;经过地理探测器的因子探测器发现,土壤pH和有机质(OC)对7种重金属含量具有较强的解释力;交互探测发现,不同影响因子交互后的结果为非线性增强或双因子增强,其中,OC和pH交互作用是重金属空间分异的主导因素,为丽江市的土壤环境健康保护和可持续发展提供重要的科学依据.

关键词：重金属污染 PMF模型地理探测器影响因子源解析

Grow defect-rich bamboo-like carbon nanotubes on carbon black for enhanced microwave absorption properties in X band

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Journal of Materials Science & Technology 2022年第24期119卷 200-208页

作者： Yameng Jiao Qiang Song Xuemin Yin liyuan han Wei li Hejun li State key Laboratory of Solidification Processing Shannxi Province Key Laboratory of Fiber Reinforced Light Composite MaterialsCarbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’an 710072China

Due to the limited electromagnetic wave(EMW)loss capacity and agglomeration,carbon black(CB)gradually fails to meet the increasingly harsh demanding ***,defect-rich bamboo-like carbon nanotubes(CNTs)were grown on CB by the process of chemical vapor *** prepared in situ on CB can assist it to build a developed multilevel conductive network and introduce plentiful CB/CNTs ***’s more,the defects that accompany the growth of CNTs endow CNTs with a moderate conductivity and good impedance matching,thereby causing an effective microwave absorption(MA).Meanwhile,the high-density defects on CNTs can induce dipole polarization to further strengthen the EMW loss *** influence of CNTs with different growth time on MA performance has been *** from the structural merits,the synthesized CB-CNT with CNTs growth time of 40 min exhibits the optimal absorbing property,which has the minimum reflection loss of-53.6 d B and maximum effective absorption bandwidth of 4.1 GHz with the thickness of 2.7 mm,covering almost the entire X *** introduction of defect-rich CNTs significantly enhances the EMW loss ability of CB,which provides a rational strategy for the design of high-efficient microwave absorption materials.

关键词： Microwave absorption Carbon nanotubes Defect-rich Conductive network Interface polarization

Characterization and source analysis of indoor/outdoor culturable airborne bacteria in a municipal wastewater treatment plant

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Journal of Environmental Sciences 2018年第12期30卷 71-78页

作者： Guangsu Xu Yunping han lin li Junxin liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

The potential health risks of airborne bacteria emission from a wastewater treatment process have been concerned. However, few studies have investigated the differences in community structure between indoor and outdoor bacteria. In this work, the characterization of airborne bacteria was studied in a municipal wastewater treatment plant in Beijing, China. Two indoor（i.e., fine screen room and sludge dewatering house） and two outdoor（i.e., aeration tank and control site） sampling sites were selected. An Andersen six-stage impactor was used for collecting culturable airborne bacteria in the air, and Illumina MiSeq sequencing was conducted to track the emission source of the culturable airborne bacteria. The results indicate that, compared with the outdoor aeration tank site, the concentrations of culturable airborne bacteria in the indoor fine screen room with poor ventilation were more than ten times higher and the particle size was about twice as large. The community structures of indoor and outdoor culturable airborne bacteria were obviously different. Enterobacteriaceae and opportunistic pathogens were detected in indoor culturable airborne bacteria, with wastewater and sludge dewatering machine identified as the primary sources. Conversely,Enterobacteriaceae and opportunistic pathogens were not detected in outdoor culturable airborne bacteria. Outdoor high wind speed might have resulted in rapid dilution and mixing of culturable airborne bacteria generated from the aeration tank with the ambient air. The results of the present research suggest that covering pollution sources, increasing ventilation rates, and using protective measures for personnel should be implemented to decrease the exposure risk to indoor culturable airborne bacteria.

关键词： Culturable airborne bacteria Community composition Emissions Pathogens Wastewater treatment plant

放牧强度对优势种群与植物群落地上现存量关系的影响

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草地学报 2024年第5期32卷 1440-1447页

作者：王梓晗吕世杰王忠武刘红梅闫宝龙王颖杰韩国栋李治国内蒙古农业大学内蒙古呼和浩特010018 内蒙古自治区林业科学研究院内蒙古呼和浩特010010 内蒙古民族大学农学院内蒙古通辽028000 内蒙古赤峰市森林草原保护发展中心内蒙古赤峰024000

为探究优势种对植物群落结构和功能的影响,本研究以内蒙古短花针茅草原为研究对象,整理不同降水年份(2014—2016年)和4个放牧试验区(对照,Control,CK;轻度放牧,light grazing,LG;中度放牧,Moderate grazing,MG;重度放牧,Heavy grazing,... 详细信息

为探究优势种对植物群落结构和功能的影响,本研究以内蒙古短花针茅草原为研究对象,整理不同降水年份(2014—2016年)和4个放牧试验区(对照,Control,CK;轻度放牧,light grazing,LG;中度放牧,Moderate grazing,MG;重度放牧,Heavy grazing,HG)下优势种群和植物群落地上现存量数据,采用对比分析和数据包络(CCR模型)分析,发现伴随放牧强度和降水量的变化,不同优势种群地上现存量的响应存在差异。LG区下的短花针茅和无芒隐子草的地上现存量高于CK、MG和HG区。冷蒿的地上现存量对放牧响应的敏感性高于短花针茅和无芒隐子草。受放牧强度影响,植物群落地上现存量由短花针茅、无芒隐子草和冷蒿这三种优势种的调控转为主要以短花针茅调控。重牧和极端干旱年份导致优势种与植物群落地上现存量的双向协调作用丧失。

关键词：荒漠草原放牧强度降水量 CCR模型地上现存量

维普期刊数据库博看期刊

A scalable and efficient IPv4 address sharing approach in IPv6 transition scenarios

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Frontiers of Information Technology & Electronic Engineering 2015年第8期16卷 634-645页

作者： Guo-liang han Cong-xiao BAO Xing li CERNET Center Tsinghua University

IPv6 has been an inevitable trend with the depletion of the global IPv4 address space. However, new IPv6 users still need public IPv4 addresses to access global IPv4 users/resources, making it important for providers to share scarce global IPv4 addresses effectively. There are two categories of solutions to the problem, carrier-grade NAT （CGN） and ＇A＋P＇（each customer shaving the same IPv4 address is assigned an excluded port range）. However, both of them have limitations. Specifically, CGN solutions are not scalable and can bring much complexity in managing customers in large-scale deployments, while A＋P solutions are not flexible enough to meet dynamic port requirements. In this paper, we propose a hybrid mechanism to improve current solutions and have deployed it in the Tsinghua University Campus Network. The real traffic data shows that our mechanism can utilize limited IPv4 addresses efficiently without degrading the performance of applications on end hosts. Based on the enhanced mechanism, we propose a method to help service providers make address plans based on their own traffic patterns and actual requirements.

关键词： IPv6 transition Carrier-grade NAT (CGN) A+P Address sharing Dynamic switching