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Fluid identification and tight oil layer classification for the southwestern Mahu Sag,junggar Basin using NMR logging-based spectrum decomposition

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Energy Geoscience 2024年第2期5卷 62-69页

作者： Wenbiao Huang Yibing Guo jun qin Zhongchen Ba Zongbin Zhang Luning Bai Heng Li School of Geosciences China University of Petroleum(East China)QingdaoShandong266580China PetroChina Xinjiang Oilfield Company KaramayXinjiang834000China

The intricate distribution of oil and water in tight rocks makes pinpointing oil layers *** conventional identification methods offer potential solutions,their limited accuracy precludes them from being effective in their applications to unconventional *** study employed nuclear magnetic resonance(NMR)spectrum decomposition to dissect the NMR T_(2)spectrum into multiple ***,it employed laboratory NMR experiments to ascertain the fluid properties of these sub-spectra,aiming to enhance identification *** findings indicate that fluids of distinct properties overlap in the T_(2)spectra,with bound water,movable water,bound oil,and movable oil appearing sequentially from the low-value zone to the high-value ***,an oil layer classification scheme was proposed,which considers the physical properties of reservoirs,oil-bearing capacity,and the characteristics of both mobility and the oil-water two-phase *** applied to tight oil layer identification,the scheme's outcomes align closely with actual test results.A horizontal well,deployed based on these findings,has produced high-yield industrial oil flow,underscoring the precision and dependability of this new approach.

关键词： Nuclear magnetic resonance Fluid identification Oil layer identification NMR T_(2)spectrum decomposition Normal distribution simulation

Stark splitting of intense red emission for Er^(3+)in O_(h) symmetry sites realizing optical temperature sensing in biological applications

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Rare Metals 2024年第3期43卷 1263-1274页

作者： Yue Guo Lin-jun qin Jing Xu Xiao-Ping Jiang Xiao-Yu Yue Yi Hou Hao Shi Li-Xi Wang Qi-Tu Zhang Collage of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing211816China

Optical temperature sensing based on the fluorescence intensity ratio(FIR)of red emission for lanthanide ions holds significant relevance in non-contact temperature measurement for biological *** this study,the perovskite-structured KZnF_(3)is utilized as a host material for Er^(3+)to achieve a high-purity upconversion(UC)red *** observed Stark splitting of the red emission peak provides evidence of the energy level splitting of Er^(3+).Group theory is employed to decompose the spectral branching of Er^(3+)under the point group symmetry of KZnF_(3),allowing for the derivation of Stark splitting energy levels induced by the crystal field *** optical temperature-sensing behavior of the red UC luminescence was investigated,specifically examining the FIR of the splitting sub-peaks,which exhibited an exponential relationship with *** KZnF_(3):Yb^(3+),Er^(3+)demonstrated a relative sensitivity(S_(r))of 0.00182%·K^(-1)at 298 K,highlighting its excellent response to *** vivo bio-thermometry experiments conducted on chicken breast validated the material's ability to penetrate biological tissues and showed its significant sensitivity of the FIR to *** results establish KZnF_(3):Yb^(3+),Er^(3+)as a promising material for optical thermometry in various biological applications.

关键词： KZnF_(3) Er^(3+) Upconversion luminescence Stark splitting Temperature sensing

CoFe_(2)O_(4) decorated graphene/C_(18)-functionalized mesoporous silica nanocomposites prepared for magnetic enrichment and electrochemical detection of promethazine in beef

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Chinese Chemical Letters 2024年第3期35卷 208-213页

作者： Xingdong Yang Shi-Ming Ying Sen Zhang Jinxia Dai Wei Gao Tian-Qi Wang jun-qin Qiao Hong-Zhen Lian Li Mao State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry&Chemical Engineering and Centre of Materials AnalysisNanjing UniversityNanjing 210023China Ministry of Education(MOE)Key Laboratory of Modern Toxicology School of Public HealthNanjing Medical UniversityNanjing 211166China

Promethazine(PHZ)is used as a sedative in veterinary medicine,and its residue can threaten the health of *** electrochemical detection of PHZ is suitable method for application in the ***,the traditional electroanalysis is difficult to perform directly in meat samples due to matrix *** work integrates magnetic solid-phase extraction and differential pulse voltammetry for highly sensitive and selective determination of PHZ in beef and beef liver for the first ***_(2)O_(4)/graphene coated with C_(18)-functionalized mesoporous silica(MG@mSiO_(2)-C_(18))is synthesized as dispersed magnetic adsorbent to extract *** glassy carbon electrode modified with nitrogen-doped hollow carbon microspheres(HCM)attracts the MG@mSiO_(2)-C_(18)with PHZ,and directly detects the PHZ without elution ***@mSiO_(2)-C_(18)can separate PHZ to avoid the interference of impurities on following detection,and also concentrate PHZ on magnetic ***,the electrode modification with HCM can amplify the electrochemical signal of ***,the integrated PHZ determination method exhibits a wide linear range from 0.08μmol/L to 300μmol/L with a low limit of detection of 9.8 nmol/*** beef sample analysis presents excellent recovery,demonstrating that this protocol is promising for the rapid and onsite detection of PHZ in real meat samples。

关键词： Promethazine(PHZ) Drug residue Magnetic solid phase extraction Electrochemical detection Beef

Perioperative complication incidence and risk factors for retroperitoneal neuroblastoma in children:analysis of 571 patients

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World Journal of Pediatrics 2024年第3期20卷 250-258页

作者： Min He Jia-Bin Cai Xuan Wu Yin-Bing Tang Jin-Yan Wang jun-qin Mao Ji-jun Chen Li-Feng Zhang Zhong-Hai Guan Jie-Ni Xiong Wan-Xin Peng Jin-Hu Wang Ting Tao Pediatric Cancer Research Center National Clinical Research Center for Child HealthHangzhouChina Department of Surgical Oncology Children's HospitalZhejiang University School of MedicineHangzhouChina Cancer Center Zhejiang UniversityNo.3333 Binsheng RodeHangzhouChina

Background Surgery plays an important role in the treatment of *** complications may impact the course of neuroblastoma *** date,comprehensive analyses of complications and risk factors have been *** Patients with retroperitoneal neuroblastoma undergoing tumor resection were retrospectively analyzed between 2014 and *** data collected included clinical characteristics,operative details,operative complications and postopera-tive *** factors for perioperative complications of retroperitoneal neuroblastoma were *** A total of 571 patients were enrolled in this *** complications were observed in 255(44.7%)*** leakage(28.4%),diarrhea(13.5%),and injury(vascular,nerve and organ;7.5%)were the most frequent *** were three operation-related deaths(0.53%):massive hemorrhage(n=1),biliary tract perforation(n=1)and intestinal necrosis(n=1).The presence of image-defined risk factors(IDRFs)[odds ratio(OR)=2.09,P<0.01],high stage of the International Neuroblastoma Risk Group staging system(INRGSS)(OR=0.454,P=0.04),retroperitoneal lymph node metastasis(OR=2.433,P=0.026),superior mesenteric artery encasement(OR=3.346,P=0.003),and inferior mesenteric artery encasement(OR=2.218,P=0.019)were identified as independent risk factors for perioperative *** Despite the high incidence of perioperative complications,the associated mortality rate was quite ***-perative complications of retroperitoneal neuroblastoma were associated with IDRFs,INRGSS,retroperitoneal lymph node metastasis and vascular *** with high-risk factors should receive more serious attention during surgery but should not discourage the determination to pursue total resection of neuroblastoma.

关键词： Complication Neuroblastoma Risk factors Surgery

A glycine-rich nuclear effector VdCE51 of Verticillium dahliae suppresses plant immune responses by inhibiting the accumulation of GhTRXH2

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The Crop Journal 2024年第4期12卷 1137-1149页

作者： Chi Li Yingqi Huang Wenjing Shang Jieyin Chen Steven J.Klosterman Krishna V.Subbarao jun qin Xiaoping Hu State Key Laboratory of Crop Stress Resistance and High-Efficiency Production Key Laboratory of Plant Protection Resources and Pest Management of Ministry of EducationKey Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture and Rural AffairsCollege of Plant ProtectionNorthwest A&F UniversityYangling 712100ShaanxiChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Western Agricultural Research Center Chinese Academy of Agricultural SciencesChangji 831100XinjiangChina Agricultural Research Service United States Department of AgricultureSalinasCA 93905USA Department of Plant Pathology University of CaliforniaDavisc/o United States Agricultural Research StationSalinasCA 93905USA

Verticillium dahliae is an important soil-borne fungal pathogen that causes great yield losses in many cash *** of this fungus are known to regulate plant immunity but the mechanism much remains unclear.A glycine-rich nuclear effector,VdCE51,was able to suppress immune responses in tobacco against Botrytis cinerea and Sclerotinia *** effector was a required factor for full virulence of ***,and its nuclear localization was a requisite for suppressing plant *** thioredoxin GhTRXH2,identified as a positive regulator of plant immunity,was a host target of *** findings show a virulence regulating mechanism whereby the secreted nuclear effector VdCE51 interferes with the transcription of PR genes,and the SA signaling pathway by inhibiting the accumulation of GhTRXH2,thus suppressing plant immunity.

关键词： Verticillium dahliae Plant immunity Effector Thioredoxin

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近20年来肥城市林地时空变化及其驱动因子

林业科学 2024年第7期60卷 40-46页

作者：李祎单博文杨丽覃钧石雷国家林业和草原局/北京市共建竹藤科学与技术重点实验室国际竹藤中心北京100102 滇南竹林生态系统国家定位观测研究站沧源677400

[目的]提取肥城市不同时期的林地信息,分析林地时空变化特征,挖掘林地面积变化的驱动因子,为区域林地资源监测、管理和可持续发展提供参考。[方法]以肥城市为研究区,基于2000-2020年21期Landsat遥感数据,首先对Landsat遥感数据进行辐射... 详细信息

[目的]提取肥城市不同时期的林地信息,分析林地时空变化特征,挖掘林地面积变化的驱动因子,为区域林地资源监测、管理和可持续发展提供参考。[方法]以肥城市为研究区,基于2000-2020年21期Landsat遥感数据,首先对Landsat遥感数据进行辐射定标、大气校正等预处理,采用决策树分类法对遥感数据进行土地类型解译,提取林地相关信息;然后揭示近20年来林地时空变化特征;最后构建新的环境压力模型(IPAT),分析林地面积变化的驱动因子。[结果]基于决策树规则提取的肥城市林地信息用户精度达94.7%,具有较高的解译精度。解译结果表明,近20年来林地面积在波动性中呈增长趋势,净增加17463.54 hm^(2);增加的林地主要分布在肥城市中部和北部矿区,减少的林地则集中分布于中部林地的边缘部分,最终呈现中部和北部集中分布、其他地区零星分布的空间特征。改进的环境压力模型(IPAT)表明,林地禀赋价值是肥城市林地面积变化的主要驱动因子(贡献率超80.3%),富裕程度是次要驱动因素,二者贡献比例超过改进IPAT模型4个因子总贡献率的92%;林业产值对国内生产总值的贡献率和人口数量对林地面积变化的影响相对较小。[结论]基于决策树分类法对遥感数据解译能够准确提取肥城市林地信息并监测林地动态变化,林地禀赋价值对林地面积变化有显著影响。

关键词：林地 Landsat数据林地禀赋价值变化 IPAT模型驱动因子

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热交换法中氦气循环利用的装置和方法研究

山西化工 2024年第2期44卷 120-121,137页

作者：秦俊江苏吉星新材料有限公司江苏扬中212216

可用于LED衬底的材料主要有硅、碳化硅、蓝宝石、氮化镓等。由于硅单晶和氮化镓晶格匹配太差无法商业化应用;碳化硅单晶成本价格较高,目前市价约是蓝宝石晶体的5倍以上;氮化镓单晶制备更困难,虽然同质外延质量最好,但价格是蓝宝石晶体... 详细信息

可用于LED衬底的材料主要有硅、碳化硅、蓝宝石、氮化镓等。由于硅单晶和氮化镓晶格匹配太差无法商业化应用;碳化硅单晶成本价格较高,目前市价约是蓝宝石晶体的5倍以上;氮化镓单晶制备更困难,虽然同质外延质量最好,但价格是蓝宝石晶体的数百倍。综上所述,预计未来30年内,蓝宝石单晶还是LED衬底材料的理想选择。目前,蓝宝石的生长方法主要有提拉法(Cz)、导模法(EFG)、泡生法(Ky)、热交换法(HEM)等。本文介绍了各种蓝宝石长晶方法,并对其优缺点进行了分析。通过分析热交换法在生长大尺寸无缺陷晶体具有明显优势,结合热交换法原理开发了氦气管道,为降低热交换法生长蓝宝石成本提供了一种可行装置和方法。

关键词：蓝宝石生长热交换法氦气循环利用装置

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面向低剂量CT的牙齿分割网络

中国图象图形学报 2024年第3期29卷 686-696页

作者：秦俊卢婷岚纪柏李雨晴长春理工大学计算机科学技术学院长春130000 吉林大学白求恩第一医院长春130000

目的锥形束计算机断层扫描(cone beam computer tomography, CBCT)已成为口腔诊疗领域中最常用的一项医学影像技术。由于CBCT图像本身对比度低且牙齿形状复杂,在进行牙齿分割时容易导致分割边界模糊、牙齿根部错误分割的问题。现有方... 详细信息

目的锥形束计算机断层扫描(cone beam computer tomography, CBCT)已成为口腔诊疗领域中最常用的一项医学影像技术。由于CBCT图像本身对比度低且牙齿形状复杂,在进行牙齿分割时容易导致分割边界模糊、牙齿根部错误分割的问题。现有方法往往无法达到预期效果,并且基于深度学习的分割网络在分割精度等性能提升到一定程度后存在生梯度爆炸、过拟合以及无法关注图像全局信息等限制。然而,牙齿分割在医生制定诊断和治疗计划方面至关重要。为了应对这一问题,提出了一种名为MF-CA Net的牙齿分割模型,以提高牙齿分割的准确性和鲁棒性。方法 MF-CA Net模型引入了多尺度特征提取模块(multi-scale feature extraction module, MFEM)和CA(coordinate attention)注意力机制,这些模块使网络能够准确地捕捉感兴趣的牙齿区域,并提取丰富而密集的多尺度特征信息,从而有效地指导分割任务。特别是在牙根分割方面,这些模块能够显著提高分割的精度。为了进一步提升分割算法的性能,还引入了联合损失函数,该损失函数综合考虑了像素级、局部级和全局级3个方向的牙齿边缘分割,以提高算法的准确性和稳健性。结果实验在数据集上对MF-CA Net模型与6种主流方法进行了比较。实验结果表明,相较于其他分割方法,MF-CA Net模型在各项评价指标上都取得了显著的提升。尽管在精度(accuracy)指标上稍低于DeeplabV3+,但在Dice评价指标上达到了0.949 5的高分数,相比PyConvU-Net提高了4%,相对于DeeplabV3+提高了约4%,对比U-Net提高了约16%。此外,平均交并比(mean intersection-over-union,mIoU)指标提升了3%~11%,F2值提升了5%。结论本文提出的MF-CA Net网络模型可以实现对牙齿的精确分割。

关键词：深度学习锥形束计算机断层扫描(CBCT) 牙齿分割注意力机制多尺度信息损失函数分割精度

长江中上游流域过去千年极端洪涝事件重建与分析

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长江流域资源与环境 2024年第1期33卷 201-213页

作者：杨巨佳覃军李骁锐陈存昕中国地质大学(武汉)环境学院湖北武汉430074

以长江中上游流域为主要研究区域,根据历史文献资料、洪水题刻和现代水位数据重建该流域过去千年极端洪涝年,分析不同时期洪涝事件发生的规律和差异,主要结论如下:(1)用历史文献和题刻重建得到截止到建国前的45个洪涝年,平均18 a发生一... 详细信息

以长江中上游流域为主要研究区域,根据历史文献资料、洪水题刻和现代水位数据重建该流域过去千年极端洪涝年,分析不同时期洪涝事件发生的规律和差异,主要结论如下:(1)用历史文献和题刻重建得到截止到建国前的45个洪涝年,平均18 a发生一次,洪涝发生的年际分布不均;(2)现代器测水位数据对重建的洪涝年延长至2002年,补充了1954、1981和1998年3个年份,得到了一份1153~2002年长江中上游流域完整的洪涝年表;(3)对洪涝事件发生频率和气候背景分析发现,近千年来长江中上流域洪涝灾害的发生频率具有一定的波动性,且近两百年来有不断增加的趋势。洪涝年的发生频次和发生机理在不同时期有所不同:中世纪暖期和小冰期主要是由于二者气候差异造成的冷暖、季风和降雨带的不同,现代暖期则主要是受到了人类活动的影响,洪水事件发生频率和强度有增无减。

关键词：长江中上游历史记录重建极端洪涝气候变化