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黄河流域油气开采废物道路利用的风险与管控限值区域差异

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环境科学研究 2024年第1期37卷 160-170页

作者：李淑徐亚赵玉鑫刘玉强孙淑娜中国环境科学研究院环境基准与风险评估国家重点实验室固体废物污染控制技术研究所北京100012 吉林建筑大学市政与环境工程学院吉林长春130118 甘肃省工业废弃物循环与调控重点实验室甘肃兰州730000

道路充填材料是油气开采废物脱油残渣(OCDRs)资源化的重要途径.现有资源化风险评估和管控主要基于简化模型,且未考虑区域风险差异,难以精准表征黄河流域OCDRs道路利用的环境风险及时空差异.本研究联合运用淋溶模拟实验、源强指数衰减模... 详细信息

道路充填材料是油气开采废物脱油残渣(OCDRs)资源化的重要途径.现有资源化风险评估和管控主要基于简化模型,且未考虑区域风险差异,难以精准表征黄河流域OCDRs道路利用的环境风险及时空差异.本研究联合运用淋溶模拟实验、源强指数衰减模型和污染物瞬态迁移扩散模型,结合Monte Carlo方法对黄河流域OCDRs路基充填条件下的风险、管控限值及区域差异开展研究.结果表明:黄河流域Cu等6种重金属的实际累积释放量大都在常规浸出方法的1%~10%左右,但部分重金属的淋溶浓度峰值高于醋酸缓冲溶液法(HJ/T 300-2007《固体废物浸出毒性浸出方法醋酸缓冲溶液法》)、硫酸硝酸法(HJ/T299-2007《固体废物浸出毒性浸出方法硫酸硝酸法》)、水平振荡法(HJ 557-2010《固体废物浸出毒性浸出方法水平振荡法》)得到的浸出浓度.风险精细评估结果表明,OCDRs在黄河流域各省区道路利用条件下暴露点浓度超标概率为0,暴露浓度(95%分位值)低于地下水Ⅲ类水质限值(gB/T 14848-2017《地下水质量标准》),风险可接受;以浸出浓度为源强预测Pb的暴露浓度是地下水Ⅲ类水质限值的4.1倍,风险估计过高.沿黄9省区污染风险差异较大,暴露浓度最大相差41.46倍(ba.;管控限值相差更大,最大值省份(宁夏回族自治区)与最小值省份(四川省)相差近50倍(Zn).对比现行的鉴别标准,计算的各污染物风险管控限值大部分低于《危险废物鉴别标准浸出毒性鉴别》(gB 5085.3-2007)限值,高于Ⅰ类固废限值,但个别省份(如宁夏回族自治区)管控限值高于gB 5085.3-2007限值.研究显示,传统浸出和风险评估方法体系对OCDRs中污染物的释放潜力和污染风险存在高估,亟待国家层面完善固废资源化风险评估和管控方法标准体系;同时,不同区域风险及管控限值差异较大,应对其中有害物质采取差异化管控要求.

关键词：脱油废物资源化区域差异风险管控

基于稀土上转换纳米粒子传感器的构建及其在食品添加剂检测中的应用

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光谱学与光谱分析 2024年第9期44卷 2459-2466页

作者：张璇王雅森温娜吕海霞李宝铭福州大学材料科学与工程学院分子材料与工程系福建福州350108

稀土上转换纳米粒子(UCNPs)因其具有毒性小、化学稳定性好和背景荧光低等优点被用于构建荧光纳米传感器。通过溶剂热法制备核壳UCNPs,采用柠檬酸钠对其进行表面配体交换得到水溶性核壳UCNPs(Cit-CS-UCNPs),以Cit-CS-UCNPs作为荧光传感... 详细信息

稀土上转换纳米粒子(UCNPs)因其具有毒性小、化学稳定性好和背景荧光低等优点被用于构建荧光纳米传感器。通过溶剂热法制备核壳UCNPs,采用柠檬酸钠对其进行表面配体交换得到水溶性核壳UCNPs(Cit-CS-UCNPs),以Cit-CS-UCNPs作为荧光传感器的能量供体,二氧化锰(MnO_(2))纳米片作为荧光传感器的能量受体,采用荧光共振能量转移(FRET)机理,构建了一种用于食品添加剂二氧化氢(H_(2)O_(2))和叔丁基对苯二酚(TBHQ)检测的荧光纳米传感器(Cit-CS-UCNPs-MnO_(2))。通过扫描电镜(SEM)、荧光光谱和紫外可见吸收光谱(UV-Vis)等分析测试手段对制备的纳米材料的形貌结构和性能进行表征。考察了猝灭剂浓度、孵育温度及孵育时间等实验条件对荧光传感体系检测性能的影响。荧光光谱和UV-Vis实验结果表明,Cit-CS-UCNPs最大发射峰位于654nm,Cit-CS-UCNPs与MnO_(2)结合后,核壳UCNPs发生荧光猝灭,当存在H_(2)O_(2)时,Cit-CS-UCNPs的荧光恢复,说明在此波段H_(2)O_(2)与MnO_(2)纳米片发生氧化还原反应,MnO_(2)纳米片被还原成Mn^(2+),逐渐从Cit-CS-UCNPs的表面解离下来;存在TBHQ时,Cit-CS-UCNPs-MnO_(2)与TBHQ体系峰位与TBHQ偏移到253nm,为TBHQ与MnO_(2)纳米片发生氧化还原反应,使得Cit-CS-UCNPs-MnO_(2)体系中FRET效应减弱,荧光强度回升。SEM结果表明,MnO_(2)纳米片均匀包覆在Cit-CS-UCNPs的周围,在水中仍可保持良好的分散性,表明MnO_(2)纳米片修饰到Cit-CS-UCNPs表面。对猝灭剂高锰酸钾(KMnO4)的浓度进行了优化。结果表明,当KMnO4浓度为10mol·L^(-1)时,猝灭效率可达90%。对检测条件进行优化,结果表明H_(2)O_(2)的检测孵育时间为25min时,MnO_(2)和H_(2)O_(2)之间氧化还原反应基本完全,Cit-CS-UCNPs-MnO_(2)荧光恢复值最大;TBHQ的检测孵育时间为30min。在最佳实验条件下,Cit-CS-UCNPs-MnO_(2)的荧光强度变化比率与H_(2)O_(2)浓度(0~1000μmol·L^(-1))及TBHQ浓度(0~0.6 mmol·L^(-1))分别具有良好的线性关系。保持最佳实验条件,选取食品中存在的代表性金属离子(如K+、Na+、Ca^(2+)和Mg^(2+))和常见的食品添加剂苯甲酸(ba.、D-葡萄糖(glu)、山梨酸钾(PS)、蔗糖(Suc)、纳他霉素(Nat)和肌醇(Ino)作为研究对象进行选择性测试,发现与H_(2)O_(2)相比,Cit-CS-UCNPs-MnO_(2)对其他添加物质没有强烈的反应,传感器整体荧光信号波动不大,因此Cit-CS-UCNPs-MnO_(2)对H_(2)O_(2)和TBHQ可进行特异性检测。

关键词：上转换纳米粒子核壳结构荧光纳米传感器

Calculation of the energy dependence of fission fragments yields and kinetic energy distributions for neutron-induced ^(235)U fission

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Chinese Physics C 2024年第8期48卷 159-169页

作者： ya-Ning Han Zheng Wei Yi-Xuan Wang Dong-Ying Huo Peng-Qi Zhang Ming Li Jun Ma Kang Wu Yong-guang Zheng Yuan He Zhi-Yong Deng Tian-Zhi Jiang Xiang-Lin Zhuo Jin Li Yun Zhang Yu Zhang Jun-Run Wang Xiao-Dong Su Ze-En yao School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China Nuclear Power Institute of China Chengdu 610000China

Fission fragments yields and average total kinetic energy are fundamental nuclear data for nuclear energy applications and the study of nuclear *** fission products,such as ^(95)Zr,^(99)Mo,^(140)ba.^(144)Ce,and ^(147)Nd,serve as burnup monitors,assessing the number of fissions induced by neutrons on ^(235)***,current experimental data for these fission products worldwide are inconsistent,introducing significant uncertainty into related scientific *** this study,we employed the Potential-driving Model to calculate the independent yields of ^(235)U and evaluate its advantages in such ***,we investigated the energy dependence of independent yields to select important ***,we calculated the cumulative yields of ^(95)Zr,^(99)Mo,^(140)ba.^(144)Ce,and ^(147)Nd,and compared them with existing literature data to explore the energy dependence of fission products for ^(235)*** the lack of fission product yield data above 14.8 MeV,we extended our calculated incident neutron energy to 20 MeV,aiming to support future scientific *** geant4 physical model does not consider the influence of incident neutron energy on the average total kinetic energy of fission fragments;thus,we introduced the excitation function of the total kinetic energy of fission fragments recommended by Madland et al.,which effectively describes the experimental data of the average total kinetic energy of fragments formed in ^(235)U *** this paper,we comprehensively discuss the energy dependence of fission product yields and average total kinetic energy.

关键词： ^(235)U(n f) potential-driving model fission yields kinetic energies energy dependence

How to manage isolated tension non-surgical pneumoperitonium during bronchoscopy?A case report

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World Journal of Clinical Cases 2022年第34期10卷 12717-12725页

作者： ya.g-Jin ba.ma Dan-Dan Shi Xing-ya Shi Li ya.g Yun-Tao Zhang ba.Sang Xiao He-yan Wang Hang-Yong He Department of Pulmonary Medicine Lhasa People’s HospitalLhasa 850013Tibet Autonomous RegionChina Department of Critical Care Medicine The Sixth Hospital of GuiyangSchool of Basic MedicineGuizhou University of Traditional Chinese MedicineGuiyang 550002Guizhou ProvinceChina Department of Respiratory and Critical Care Medicine Beijing Institute of Respiratory MedicineBeijing Key Laboratory of Respiratory and Pulmonary CirculationBeijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

ba.KgROUND Tension pneumoperitonium is a rare complication during bronchoscopy that can cause acute respiratory and hemodynamic failure,with fatal *** pneumoperitonium during bronchoscopy usually results from ruptures of the abdominal viscera that need surgical ***-surgical pneumoperitoneum(NSP)refers to some pneumoperitoneum that could be relieved without surgery and only by conservative ***,the clinical experience of managing tension pneumoperitonium during bronchoscopy is limited and *** SUMMARY A 51-year-old female was admitted to our hospital for cough with bloody sputum of seven *** the 8th day of her admission,a bronchoscopy was arranged for bronchial-alveolar lavage to detect possible pathogens in the lower respiratory tract,as oxygen was delivered via a 12 F nasopharyngeal cannula,approximately 5-6 cm from the tip of the catheter,with a flow rate of 5-10 L/*** four minutes of bronchoscopy,the patient suddenly vomited 20 mL of water,followed by severe abdominal pain,while physical examination revealed obvious abdominal distension,as well as hardness and tenderness of the whole abdomen,which was considered pneumoperitonium,and the bronchoscopy was terminated immediately.A computer tomography scan indicated isolated tension pneumoperitonium,and abdominal decompression was performed with a drainage tube,after which her symptoms were relieved.A multidisciplinary expert consultation discussed her situation and a laparotomy was suggested,but finally refused by her *** had no signs of peritonitis and was finally discharged 5 d after bronchoscopy with a good *** The possibility of tension pneumoperitonium during bronchoscopy should be guarded against,and given its serious clinical consequences,cardiopulmonary instability should be treated *** strategies could be adopted according to whether it is complicated with pneumothorax or pneumomediastinum,and the presence of p

关键词： Pneumoperitonium Tension Isolated Non-surgical Bronchoscopy Case report

白桦叶片和细根非结构性碳水化合物对火后时间的响应

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植物生态学报 2024年第6期48卷 780-793页

作者：蔡慧颖李兰慧林阳梁亚涛杨光孙龙东北林业大学林学院东北林业大学森林生态系统可持续经营教育部重点实验室哈尔滨150040

火是制约植物生长发育的重要干扰因子,影响植物的生理代谢,甚至导致植物死亡。非结构性碳水化合物(NSC)主要包括可溶性糖(SS)和淀粉(ST),对植物在干扰下存活具有重要作用。然而,关于植物NSC及其组分含量对火后时间响应机制的研究尚有不... 详细信息

火是制约植物生长发育的重要干扰因子,影响植物的生理代谢,甚至导致植物死亡。非结构性碳水化合物(NSC)主要包括可溶性糖(SS)和淀粉(ST),对植物在干扰下存活具有重要作用。然而,关于植物NSC及其组分含量对火后时间响应机制的研究尚有不足。该研究采用“空间替代时间”的方法,在大兴安岭呼中区选取5个不同火烧时间的重度火烧地块和1个临近的未火烧地块,分别采集白桦(Betula platyphylla)的叶片、细根以及根际土壤样品,测定白桦叶片和细根的NSC及其组分含量、白桦叶片和细根的性状特征,以及根际土壤属性。结果表明:白桦叶片ST和NSC含量随火后时间的增加显著降低,而细根ST和NSC含量随火后时间的增加显著增加,叶片和细根的NSC含量分别在火后30年和火后17年与火烧前无显著差异,表明细根NSC含量从重度火烧干扰的影响中恢复得更快;火后时间对白桦叶片的NSC含量有直接影响,还通过影响比叶面积对叶片的NSC含量产生间接影响;火后时间对白桦细根NSC含量的影响主要是通过影响土壤pH和比叶面积间接产生。综上,火后时间对植物NSC含量的影响具有明显的器官差异性。该结果可为火烧迹地的植被恢复研究提供科学数据和理论基础。

关键词：火后恢复淀粉可溶性糖土壤属性植物性状

Secondary coronary artery ostial lesions:Three case reports

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World Journal of Clinical Cases 2022年第20期10卷 7045-7053页

作者： Xiao-Ping Liu Hai-Jun Wang Jin-Liang gao guo-Li Ma Xin-Yun Xu Li-Na Ji Rui-Xia He ba.ya-Er Qi Li-Cheng Wang Chang-Qing Li ya-Jiang Zhang Yu-ba. Feng Department of Cardiology Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina Laboratory of Molecular Medicine Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina Department of Radiology Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina

ba.KgROUND Atherosclerosis is one of the main causes of coronary artery ostial lesions seen *** coronary artery ostial lesions are rare,and cases reported previously were associated with syphilitic vasculitis and aortic ***,we report three rare cases of secondary coronary ostial *** to their rareness,these lesions can easily be neglected,which may lead to misdiagnosis and missed *** SUMMARY We present three patients with acute myocardial infarction and unstable angina caused by secondary coronary artery ostial *** Case 1,coronary angiography(CAg)revealed 90%stenosis of the left main coronary *** contrast computed tomography(CT)suggested thymic carcinoma invading the left main coronary *** artery bypass grafting and tumor resection were *** Case 2,echocardiography revealed a sinus of Valsalva aneurysm(SVA)-like *** showed a right coronary sinus giant aneurysm and complete obstruction of the right coronary artery(RCA)*** contrast CT confirmed these *** Bentall procedure was *** Case 3,CT CAg identified an anomalous origin of the right coronary artery(AORCA)from the left sinus of Valsalva coursing between the aorta and pulmonary trunk,causing severe RCA ostium stenosis by *** correction of the AORCA was *** The cases reported here suggest that we should consider other causes of coronary ostial lesions other than atherosclerosis.

关键词： Coronary artery Ostial lesions Thymic carcinoma Sinus of Valsalva aneurysm Anomalous origin Case report

Optimal livelihood strategy for different poverty groups among farmers: a case study of the Qin-ba.Mountain area in South-Shaanxi, China

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Journal of Mountain Science 2020年第5期17卷 1206-1220页

作者： SU Fang YIN ya-juan School of Economics and Management Shaanxi University of Science&TechnologyXi'an 710021China

Achieving sustainable livelihood is the ultimate goal of poverty alleviation efforts in mountainous areas,and selecting an optimal livelihood strategy for different poverty-type farmers greatly improves farmers’livelihood capital,resists livelihood risks,and promotes sustainable *** farmers,optimal livelihood strategy means better employment opportunities,higher family income(or better income structure),and stronger employability or development *** paper classifies different types of farmers’poverty on the ba.is of a quantitative evaluation of farmers’livelihood capital in the Qin-ba.Mountain Area in South-Shaanxi by using the k-means clustering method and subsequently the fuzzy evaluation method to evaluate the effectiveness of farmers’livelihood ***,the multi-attribute decision-making model is used to analyze the selection of optimal livelihood strategies for different poverty-type *** results suggest a significant difference in the selection of the optimal livelihood strategy for different poverty-type *** without financial and human capital choose to"go out to work,"farmers lacking natural capital choose to"acquire social insurance and government relief,"farmers without physical capital choose to"use loans,"and farmers lacking social capital choose to"use savings."Studying the selection of optimal livelihood strategies for different poverty-type farmers can help to propose targeted sustainable livelihood optimization programs for farmers and accelerate efforts to overcome poverty in mountainous areas.

关键词： Optimal strategy Livelihood capital Effectiveness evaluation Qin-ba.Mountain Area Shaanxi

滇中富碱斑岩风化成土过程中元素地球化学行为及其主控因素

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地质论评 2024年第2期70卷 512-528页

作者：徐磊赵萌生程琰勋潘江涛管继云张亚徐杰陈伟志王浩宇黄加忠杨明龙巴永王守营中国地质调查局昆明自然资源综合调查中心昆明650100 自然资源部自然生态系统碳汇工程技术创新中心昆明650100

富碱斑岩带分布较广,目前对其风化过程中的元素地球化学行为研究较少。笔者等以滇中姚安富碱斑岩为例,通过对其化学风化过程的研究,有助于了解富碱斑岩成土过程中元素富集贫化控制因素,丰富碱性岩浆岩风化成土理论。笔者等分析了富碱斑... 详细信息

富碱斑岩带分布较广,目前对其风化过程中的元素地球化学行为研究较少。笔者等以滇中姚安富碱斑岩为例,通过对其化学风化过程的研究,有助于了解富碱斑岩成土过程中元素富集贫化控制因素,丰富碱性岩浆岩风化成土理论。笔者等分析了富碱斑岩风化过程中的矿物风化特征、元素含量分布特征、化学风化趋势、元素迁移富集特征及主控因素,结果表明:富碱斑岩各风化层元素含量与基岩具有继承性,体现了原位风化的特征,符合北亚热带季风气候下云南境内上扬子地块岩石的风化特征;与大陆上地壳组成(UCC)相比,风化成土过程中Ca、Na、K等阳离子强烈淋失亏损,Fe、Al富集;化学风化过程主要发生脱Ca、Na、K、Mg、Si与富Al、Fe作用,风化早期主要为去Ca、去Na过程,风化中、晚期为去K、去Mg、富Al、富Fe过程,并伴随着强烈的脱硅作用;结合迁移系数,常量元素活动性强弱顺序为:Ca>Na>K>Mg>Si>Al>Fe;微量元素地球化学行为一方面主要受地球化学性质相似的常量元素行为控制,另一方面受Al、Fe氧化物/氢氧化物和黏土矿物吸附作用的影响,Sm、Nb、Sc、Th、Ti、U、Y、Cu、Cr、Ni随风化原地残余富集,ba.Rb、Sr与K、Na、Ca、Mg等常量元素行为一致,随风化而淋失迁出。

关键词：富碱斑岩化学风化常量元素成土过程地球化学行为主控因素姚安

可见、近红外光谱和深度学习CNN-ELM算法的煤炭分类

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光谱学与光谱分析 2018年第7期38卷 2107-2112页

作者： LE ba.Tuan 肖冬毛亚纯宋亮何大阔刘善军东北大学信息科学与工程学院辽宁沈阳110004 东北大学资源土木与工程学院辽宁沈阳110004 Control Technology College Le Quy Don Technical UniversityHanoi 100000Vietnam

煤是工业的主要能源,煤的品质对工业和环境起决定性作用。在使用煤的过程中,如果不能准确确定煤的品种,有可能对生产效率、环境污染、经济损失等会造成重大的影响。传统的煤分类,主要依靠人工方法和化学分析方法,这些方法的缺点是高成... 详细信息

煤是工业的主要能源,煤的品质对工业和环境起决定性作用。在使用煤的过程中,如果不能准确确定煤的品种,有可能对生产效率、环境污染、经济损失等会造成重大的影响。传统的煤分类,主要依靠人工方法和化学分析方法,这些方法的缺点是高成本和耗费时间。如何快速准确确定煤的品质很重要。因此,提出深度学习、极限学习机-ELM算法和可见、红外光谱联合建立煤矿分类模型。首先,从抚顺、伊敏和河南夹津口煤矿区采取不同煤样品,并使用美国Spectra Vista公司的SVC HR-1024地物光谱仪测得光谱数据。然后利用深度学习的卷积神经网络-CNN提取光谱特征,并采用ELM算法对光谱数据建立分类模型。最后,为进一步提高分类精度,引入粒子群算法。通过全新定义惯性权重和加速系数的取值范围来改进粒子群算法,并使用改进粒子群算法优化CNN-ELM网络。实验结果表明,和PCA特征提取方法比较,CNN网络能够更好的提取光谱特征,CNN-ELM分类模型有良好的分类效果;改进ELM分类模型的分类精度高于基础ELM和SVM分类模型。与传统的化学分析方法和人工方法相比,此方法在经济、速度、准确性方面均具有无可比的优势。

关键词：可见、近红外光谱煤卷积神经网络粒子群极限学习机