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阜阳市集中式地下水饮用水源地水化学特征及成因分析

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环境科学 2025年第2期46卷 796-808页

作者：苏贵芬刘桂建刘玥林深安徽省地质环境监测总站合肥230001 中国科学技术大学合肥230026 中国环境科学研究院北京100012 安徽省地勘局第一水文工程地质勘查院蚌埠233000

地下水是阜阳市重要饮用水源,其水化学特征关系到居民饮水健康安全.为研究阜阳地区集中式地下水饮用水源地的水化学特征及成因机制,采集了阜阳市地下饮用水源地地下水样84组,运用数理统计、Piper三线图、Gibbs图、相关性分析、离子比例... 详细信息

地下水是阜阳市重要饮用水源,其水化学特征关系到居民饮水健康安全.为研究阜阳地区集中式地下水饮用水源地的水化学特征及成因机制,采集了阜阳市地下饮用水源地地下水样84组,运用数理统计、Piper三线图、Gibbs图、相关性分析、离子比例系数和因子分析等方法,揭示了该区地下水水化学特征、水化学组分形成机制及控制因素.结果表明,阜阳市集中式地下水饮用水源地水体为中性偏碱性水、高矿化度水,水化学类型为HCO_(3)-Na型;地下水离子特征受“岩石风化”和“蒸发作用”双重影响,其中“岩石风化”更为明显,地下水离子组成会受到外因作用发生改变;地下水中Na^(+)-Cl^(-)、F^(-)-B^(3+)、Ca^(2+)-Mg^(2+)、SO_(4)^(2-)-Cl^(-)和Na^(+)-SO_(4)^(2-)离子来源相同,Ca^(2+)-Na^(+)、Ca^(2+)-HCO_(3)^(-)和Mg^(2+)-HCO_(3)^(-)的离子来源不同,Ca^(2+)-SO_(4)^(2-)呈弱相关,不能大量共存;地下水组分主要受到含水层岩石矿物溶滤作用、阳离子交替吸附作用,地下水中Ca^(2+)和Mg^(2+)主要来源于方解石的溶解,Na^(+)来源于钠长石等含钠矿物岩石的风化溶解,含钠矿物的Na^(+)与地下水中的Ca^(2+)和Mg^(2+)发生交换反应,使Na^(+)浓度增加并在地下水中富集,而Ca^(2+)和Mg^(2+)浓度降低;地下水超采、工农业生产以及生活污水等会对地下水质量造成影响.

关键词：集中式地下水饮用水源地水化学特征水化学形成作用成因机制控制因素

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绿色金融发展对企业碳排放的影响

金融理论探索 2025年第1期 42-56页

作者：申琳李浩楠杭州电子科技大学经济学院浙江杭州310018

作为传统金融的延伸,绿色金融的碳减排作用受到实践者与政策制定者的广泛关注,但学者们对于绿色金融能否抑制碳排放的研究结论并未达成一致。本文通过构建更加完善的绿色金融测度综合评价体系,基于2000—2021年上市企业微观数据,实证考... 详细信息

作为传统金融的延伸,绿色金融的碳减排作用受到实践者与政策制定者的广泛关注,但学者们对于绿色金融能否抑制碳排放的研究结论并未达成一致。本文通过构建更加完善的绿色金融测度综合评价体系,基于2000—2021年上市企业微观数据,实证考察了绿色金融发展对企业碳排放的影响。研究发现,绿色金融的发展显著降低了企业碳排放;在考虑了环保税的调节作用后,绿色金融的碳减排效果更加明显;尤其是在中、高税率地区,环保税的调节效应更为显著。此外,绿色金融对西部地区企业、重污染企业、高新技术企业以及非“漂绿”企业的碳排放抑制效果更为突出。因此,应该进一步完善绿色金融评价体系,不断优化环保税政策,并推出差异性的绿色金融政策,同时强化监管以更好地驱动绿色发展和实现“双碳”目标。

关键词：绿色金融碳排放环保税绿色技术创新

Time delay compensation in lateral-directional flight control systems at high angles of attack

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Chinese Journal of Aeronautics 2021年第4期34卷 1-18页

作者： lin shen Da HUANG Genxing WU Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

The previous studies of time delay compensation in flight control systems are all based on the conventional aerodynamic derivative model and conducted in longitudinal motions at low angles of *** this investigation,the effects of time delay on the lateral-directional stability augmentation system in high-a regime are discussed based on theβmodel,which is proposed in our previous work and proved as a more accurate aerodynamic model to reveal the lateraldirectional unsteady aerodynamic characteristics at high angles of *** theβmodel and the quasi-steady model are used for simulating the effects of time delay on the flying qualities in high-a *** comparison between the simulation results shows that the flying qualities are much more sensitive to the mismatch of feedback gains than the state errors caused by time *** a typical adaptive controller based on the conventional dynamic derivative model and a gain-prediction compensator based onβmodel are designed to address the time delay in different *** simulation results show that the gain-prediction compensator is much simpler and more efficient at high angles of ***,the gain-prediction compensator is combined with a linearizedβmodel reference adaptive controller to compensate the adverse effects of very large time delay,which exhibits excellent performance when addressing the extreme conditions at high angles of attack.

关键词： Adaptive control Flying quality High angles of attack Time delay Yaw-roll coupling

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

紫外吸收光谱法测定天然气中硫化氢含量国际标准进展

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石油与天然气化工 2025年第01期54卷 142-148页

作者：沈琳周理宋柯静敬豪刘冬中国石油西南油气田公司天然气研究院国家市场监督管理总局重点实验室(天然气质量控制和能量计量) 中国石油天然气集团公司天然质量控制和能量计量重点实验室中国石油西南油气田公司川中油气矿

目的探索天然气分析方法国际标准制定过程，分享国际标准ISO 11626:2024《天然气含硫化合物的测定用紫外吸收光谱法测定硫化氢含量》制定经验，规范该技术在国际领域的应用。方法对采用色谱柱预分离的间接检测技术和无需色谱分离直接... 详细信息

目的探索天然气分析方法国际标准制定过程，分享国际标准ISO 11626:2024《天然气含硫化合物的测定用紫外吸收光谱法测定硫化氢含量》制定经验，规范该技术在国际领域的应用。方法对采用色谱柱预分离的间接检测技术和无需色谱分离直接检测的两种检测原理的紫外吸收光谱法的检测限、准确性、精密度进行实验研究。结果验证了紫外吸收光谱法具备准确、快速检测天然气中H2S含量的能力，总结了制定紫外吸收光谱法测定天然气中H2S含量国际标准的经验。结论提出的国际标准制定历程对今后天然气中含硫化合物含量的国际标准化分析工作思路具有参考意义。

关键词：天然气硫化氢紫外吸收光谱法在线检测国际标准

Liquid biopsy: a powerful tool to monitor trastuzumab resistance in HER2-positive metastatic gastric cancer

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Cancer Communications 2018年第1期38卷 770-772页

作者： lin shen Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital and InstituteFu-Cheng Road 52Hai-Dian DistrictBeijing 100142China

Human epidermal growth factor receptor 2(HER2)over-expression/amplification affects about 6.1%-23.0%of gastric cancer patients[1,2].All major guidelines rec-ommend HER2 testing to guide the selection for trastu-zumab treatment in metastatic gastric cancer(mGC)[3],because doublet chemotherapy with trastuzumab sig-nificantly improved overall survival(OS)in the crucial trastuzumab for gastric cancer trial(the ToGA trial)[4].However,the unsatisfactory gain of median progression-free survival(PFS)stresses important issues of intrinsic and acquired resistance to HER2-targeted therapies[4].Currently,the underlying molecular mechanism of tras-tuzumab resistance in mGC is still unclear,and the strat-egies to real time monitor resistance-specific aberrations are urgently needed.

关键词： HER2 trastuzumab chemotherapy

Effects of yaw-roll coupling ratio on lateraldirectional aerodynamic characteristics

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Chinese Journal of Aeronautics 2019年第2期32卷 272-280页

作者： lin shen Da HUANG Genxing WU College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

Experimental investigation of large amplitude yaw-roll coupled oscillations was conducted in a low-speed wind tunnel using an aircraft configuration model. A special test rig was designed and constructed to provide different coupled motions from low to high angles of attack.A parameter ‘‘coupling ratio" was introduced to indicate the extent of yaw-roll coupling. At each pitch angle, seven coupling ratios were designed to study the yaw-roll coupling effects on the lateraldirectional aerodynamic characteristics systematically. At high angles of attack, the damping characteristics of yawing and rolling moments drastically varied with coupling ratios. In the coupled motions with the rotation taking place about the wind axis, the lateral-directional aerodynamic moments exhibited unsteady characteristics and were different from the ‘‘quasi-steady" results of the rotary balance tests. The calculated results of the traditional aerodynamic derivative method were also compared with the experimental data. At low and very high angles of attack, the aerodynamic derivative method was applicative. However, within a wide range of angles of attack, the calculated results of aerodynamic derivative method were inconsistent with the experimental data, due to the drastic changes of damping characteristics of lateral-directional aerodynamic moments with yaw-roll coupling ratios.

关键词： High angles of attack Hysteresis Lateral-directional aerodynamic characteristics Unsteady Yaw-roll coupling

Effects of yaw-roll coupling ratio on the lateral-directional departure prediction and restraint

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Chinese Journal of Aeronautics 2019年第10期32卷 2239-2253页

作者： lin shen Da HUANG Genxing WU College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The experimental data obtained from yaw-roll coupled wind tunnel tests are used for lateral-directional departure prediction,by linearizing the_b model to extract nominal dynamic derivatives at each coupling *** prediction results are compared with those of the existing engineering methods which are based on the conventional aerodynamic *** comparison shows that the yaw-roll coupling ratio has a great influence on the departure *** departure resistance will loss in partial region of the coupling ratio when the angle of attack is higher than a critical *** to the stable and unstable regions of coupling ratio,a two-segment stability augmentation system with two different feedback gain matrices is obtained by pole-placement *** two-segment stability augmentation system is used in the simulations of straight and level flight,steady turn,spin recovery and Herbst *** simulation results are also compared with the applications of a fixed-gain stability augmentation system designed by the conventional aerodynamic *** the yaw-roll coupling effects are fully considered,the two-segment stability augmentation system is more effective for departure restraint and can provide a better flying quality with less control energy.

关键词： Lateral-directional departure Stability augmentation system Stability criterion Unsteady aerodynamics Yaw-roll coupling

Nanozyme-Triggered Cascade Reactions from Cup-Shaped Nanomotors Promote Active Cellular Targeting

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Research 2022年第3期2022卷 117-131页

作者： Xin Wang Zhongju Ye shen lin lin Wei Lehui Xiao State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Chemical Biology&Traditional Chinese Medicine Research Key Laboratory of Phytochemical R&D of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410082China

Self-propelled nanomotors have shown enormous potential in biomedical ***,we report on a nanozymepowered cup-shaped nanomotor for active cellular targeting and synergistic photodynamic/thermal therapy under nearinfrared(NIR)laser *** nanomotor is constructed by the asymmetric decoration of platinum nanoparticles(PtNPs)at the bottom of gold nanocups(GNCs).PtNPs with robust peroxidase-(POD-)like activity are employed not only as propelling elements for nanomotors but also as continuous O_(2)generators to promote photodynamic therapy via catalyzing endogenous H_(2)O_(2)*** to the Janus structure,asymmetric propulsion force is generated to trigger the shortranged directional diffusion,facilitating broader diffusion areas and more efficient cellular searching and *** cascade strategy combines key capabilities,i.e.,endogenous substrate-based self-propulsion,active cellular targeting,and enhanced dual-modal therapy,in one multifunctional nanomotor,which is crucial in advancing self-propelled nanomotors towards eventual therapeutic agents.

关键词： endogenous shaped Active