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Effects of soil shrinkage in permanent gullies formation: The case of Benggang erosion in the granite area of southern China

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Journal of Mountain Science 2021年第9期18卷 2328-2344页

作者： huaNG Wan-xia DENG Yu-song CAI Chong-fa jiang dai-hua Forestry College Guangxi UniversityNanning 530004China Resources and Environment College Huazhong Agricultural UniversityWuhan 430070China Agricultural College Guangxi UniversityNanning 530004China

Soil shrinkage is an important factor in slope destabilization in granitic areas, which is also one of the most important conditions for the formation of permanent gullies. This study explored the effect of soil shrinkage on permanent gullies, and Benggang erosion in granitic areas in southeastern China was used as an example. Three types of Benggang in granitic area were selected to examine the soil shrinkage of three soil layers(the lateritic, transitional and sandy layers) and their effect on the development of Benggang erosion was studied. The results show that the maximum values of COLEH and COLEV(coefficient of linear extensibility in horizontal and vertical directions, respectively) are 3.09% and 1.60% in the laterite layers, 2.71% and 2.13% in transition layers, and 1.10% and 1.82% in sandy layers, indicating that the shrinkage potential of the soil layers exhibits the following order, from highest to lowest: the laterite layer, transition layer, and sandy layer. With a decreasing volumetric water content, the linear shrinkage ratio increases gradually and eventually stabilizes, and in the laterite, transition and sandy layers, the average values of the maximum linear shrinkage are 1.50%, 2.09%, and 1.74%, respectively. Axial shrinkage is most obvious in the transition layers, in which the volume change in the form of subsidence is greater than that in other layers. The soil shrinkage curves fit the trilinear model(R2>0.9), and the soil shrinkage characteristic curves were divided into structural, basic, and residual sections. The correlation analysis shows that the soil shrinkage rate is positively correlated with clay and Fe2 O3 content and negatively correlated with sand content. Clay and sand contents are the most important factors influencing soil shrinkage. Soil oxides can influence soil shrinkage by affecting the particle composition of the soil, so soil shrinkage is closely related to soil clay minerals. Our findings can provide a theoretical basis for revealing the mechanism of Benggang erosion a

关键词： Soil shrinkage Permanent gully Granite Benggang Soil layers

不同矿物调理剂对Cd污染水田土壤性质及水稻Cd含量的影响

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西南农业学报 2024年第3期37卷 597-603页

作者：李少华潘荣祝陆贵佳何烨蒋代华黄智刚广西大学农学院/广西农业环境与农产品安全重点实验室南宁530004 内蒙古大学创业学院呼和浩特010000 黑龙江大学现代农业与生态环境学院哈尔滨154000

【目的】探究不同矿物调理剂对广西镉(Cd)污染水田土壤性质及水稻Cd含量的影响,为利用水田生产安全稻米提供参考依据。【方法】选用钙镁硅调理剂A和B、钙硅调理剂C和钙镁调理剂D(分别设为A、B、C和D处理),在广西某受Cd污染水田开展Cd污... 详细信息

【目的】探究不同矿物调理剂对广西镉(Cd)污染水田土壤性质及水稻Cd含量的影响,为利用水田生产安全稻米提供参考依据。【方法】选用钙镁硅调理剂A和B、钙硅调理剂C和钙镁调理剂D(分别设为A、B、C和D处理),在广西某受Cd污染水田开展Cd污染大田修复治理试验,以不施用调理剂为对照(CK)。处理后于水稻成熟期测定土壤的pH、阳离子交换量(CEC)、总Cd和土壤有效态Cd含量及水稻根、茎、叶和籽粒的Cd含量,分析不同矿物调理剂对Cd污染水田土壤的修复治理效果及Cd在水稻各部位的残留状况,并对土壤总Cd含量、CEC和pH与有效态Cd含量进行相关分析。【结果】施用矿物调理剂可显著提高Cd污染水田的土壤pH和CEC(P<0.05,下同),二者分别较CK提高15.0%~16.6%和20.4%~23.8%;可显著降低Cd污染水田的土壤有效态Cd含量,较CK下降14.0%~19.3%。施用矿物调理剂后水田的土壤有效态Cd含量与pH呈显著负相关,pH的对数ln(pH)值与土壤有效态Cd含量的相关系数为0.4053;ln(pH)值与CEC呈极显著负相关(P<0.01),相关系数为0.6326;随着土壤pH和CEC的上升,土壤有效态Cd含量持续下降。施用矿物调理剂均可有效降低水稻根、茎、叶和籽粒的Cd含量及水稻地上部Cd的富集系数,其中,水稻籽粒的总Cd含量下降35.9%~50.2%,水稻地上部(茎、叶和籽粒)Cd的富集系数分别下降19.5%~33.5%、32.1%~44.9%和38.6%~52.6%。【结论】施用不同矿物调理剂均可显著提升水田土壤pH和CEC,从而降低土壤有效态Cd含量,抑制Cd从土壤向水稻根、茎、叶和籽粒迁移,有效降低水稻Cd含量,减少Cd在水稻地上部(茎、叶和籽粒)富集。

关键词： Cd污染水田矿物调理剂修复治理水稻安全稻米

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Exploration of Strong Metal-Support Interaction in Heterogeneous Catalysts by in situ Transmission Electron Microscopy

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Chinese Journal of Chemistry 2024年第9期42卷 1004-1008页

作者： Yongjun jiang Sheng dai Key Laboratoryfor Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The phenomenon of strong metal-support interaction(SMSI)observed in supported metal catalysts,usually accompanied by the formation of the encapsulation layer on metal nanoparticles,has attracted extensive research attention due to its significance in heterogeneous catalysis.Notably,great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy(TEM),along with an enhanced comprehension of the underlying mechanisms governing SMSI formation.This emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions.A brief perspective about the use of in situ TEM for further study of SMSI is also presented,showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts.

关键词： Heterogeneous catalysis In situ TEM Strong metal-support interaction Structure changes Interfaces Structural evolution

Study on a conical bearing for acceleration-sensitive equipment

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 103-128页

作者： Pang Hui Xu Wen dai Junwu jiang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China School of Civil Engineering and Transportation Beihua UniversityJilin 132013China

Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during earthquakes.However,isolation strategies give less attention to acceleration-sensitive systems or equipment.Meanwhile,as the isolation layer’s displacement grows,the stiffness and frequency of traditional rolling and sliding isolation bearings increases,potentially causing self-centering and resonance concerns.As a result,a new conical pendulum bearing has been selected for acceleration-sensitive equipment to increase self-centering capacity,and additional viscous dampers are incorporated to enhance system damping.Moreover,the theoretical formula for conical pendulum bearings is supplied to analyze the device’s dynamic parameters,and shake table experiments are used to determine the proposed device’s isolation efficiency under various conditions.According to the test results,the newly proposed devices have remarkable isolation performance in terms of minimizing both acceleration and displacement responses.Finally,a numerical model of the isolation system is provided for further research,and the accuracy is demonstrated by the aforementioned experiments.

关键词： seismic isolation acceleration-sensitive equipment the conical pendulum bearing shake table tests isolation performance,numerical model

Fecal microbiota transplantation for irritable bowel syndrome:Current evidence and perspectives

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World Journal of Gastroenterology 2024年第16期30卷 2179-2183页

作者： Cong dai Yu-Hong huang Min jiang Department of Gastroenterology First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

In this editorial we comment on the article published in the recent issue of the World journal of Gastroenterology.We focus specifically on the mechanisms underlying the effects of fecal microbiota transplantation(FMT)for irritable bowel syndrome(IBS),the factors which affect the outcomes of FMT in IBS patients,and challenges.FMT has emerged as a efficacious intervention for clostridium difficile infection and holds promise as a therapeutic modality for IBS.The utilization of FMT in the treatment of IBS has undergone scrutiny in numerous randomized controlled trials,yielding divergent outcomes.The current frontier in this field seeks to elucidate these variations,underscore the existing knowledge gaps that necessitate exploration,and provide a guideline for successful FMT implementation in IBS patients.At the same time,the application of FMT as a treatment for IBS confronts several challenges.

关键词： Fecal microbiota transplantation Irritable bowel syndrome Microbiota Randomized controlled trial Meta-analysis

The Limitations and Ethical Considerations of ChatGPT

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Data Intelligence 2024年第1期6卷 201-239页

作者： Shangying hua Shuangci Jin Shengyi jiang Guangdong University of Foreign Studies Guangzhou 510000China

With the advancements of artificial intelligence technology,ChatGPT,a new practice of artificial intelligence,holds immense potential across multiple fields.Its user-friendly human-machine interface,rapid response capabilities,and delivery of high-quality answers have attracted considerable attention and widespread usage.Regarded by many as a groundbreaking advancement in AI,ChatGPT represents a new milestone in the field.However,as with any technological evolution,the emergence of ChatGPT brings not only benefits,but also inevitable security risks and ethical issues.This paper provides specific information about ChatGPT,including its technology,limitations,ethical issues,governance paths and future directions.Specifically,we firstly offered a thorough exploration of the technical implementation details of GPT series models.Next,we provided an intricate analysis elucidating the reasons for limitations and scrutinized the consequential impacts,such as malicious misuse,privacy violation,and so on.Finally,we explore diverse governance paths to mitigate the impacts of ChatGPT and present future directions.This review aims to equip users with crucial knowledge,facilitating well-informed decision-making,effectively handling of potential challenges in employing ChatGPT,and staying abreast with the rapidly evolving landscape of this technology.

关键词： ChatGPT ChatGPT Technology Limitations Ethical considerations Artificial Intelligence

Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science China(Information Sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin jiang Changchun hua Junpeng LI Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are zero.Accordingly and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) condition.Therefore, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ensured.Finally, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

(Parallel) kinetic resolution of 3,3-disubstituted indolines via organocatalyzed reactions with azodicarboxylates

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Science China Chemistry 2024年第3期67卷 973-980页

作者： Qianwen jiang Dekun Zhang Mengyao Tang hua Liu Xiaoyu Yang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

A novel kinetic resolution(KR) method has been developed for 3,3-disubstituted indolines, whose catalytic asymmetric synthesis remains a significant challenge in organic synthesis. The key to the success of this KR protocol lies in the utilization of chiral phosphoric acid-catalyzed triazane formation reaction with azodicarboxylates, which enables the enantioselective synthesis of various substituted indolines bearing C3-quaternary stereocenters with good to high enantioselectivities(with sfactors up to 70). Moreover, an intriguing parallel kinetic resolution(PKR) has been developed by combining triazane formation and dehydrogenation reactions using different azodicarboxylates. Experimental studies have provided insight into the mechanism of this PKR reaction, demonstrating stereoselectivity in both triazane formation and dehydrogenation steps, favoring the opposite enantiomers. The large-scale synthesis and diverse derivatizations of the products, particularly the imine groupcontaining 3H-indoles, demonstrate the value of these(P)KR methods.

关键词： asymmetric organocatalysis kinetic resolution 3 3-disubstituted indolines azodicarboxylate triazanes

Cisplatin-based miRNA delivery strategy inspired by the circCPNE1/miR-330-3p pathway for oral squamous cell carcinoma

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2748-2760页

作者： hua-yang Fan Ming-da Zhao Hong-jie jiang Zhen-wei Yu Yu-jiang Fan Xin-hua Liang Ya-ling Tang Yong Sun State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Oral and Maxillofacial Surgery West China Hospital of StomatologySichuan UniversityChengdu 610041China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610065China State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Oral Pathology West China Hospital of StomatologySichuan UniversityChengdu 610041China

Circular RNAs(circRNAs)are ideal biomarkers of oral squamous cell carcinoma(OSCC)because of their highly stable closed-loop structure,and they can act as microRNA(miRNA)sponges to regulate OSCC progression.By analyzing clinical samples,we identified circCPNE1,a dysregulated circRNA in OSCC,and its expression level was negatively correlated with the clinical stage of OSCC patients.Gain-of-function assays revealed the tumor-suppressive effect of circCPNE1,which was then identified as a miR-330-3p sponge.MiR-330-3p was recognized as a tumor promoter in multiple studies,consistent with our finding that it could promote the proliferation,migration,and invasion of OSCC cells.These results indicated that selective inhibition of miR-330-3p could be an effective strategy to inhibit OSCC progression.Therefore,we designed cationic polylysine-cisplatin prodrugs to deliver antagomiR-330-3p(a miRNA inhibitory analog)via electrostatic interactions to form PP@miR nanoparticles(NPs).Paratumoral administration results revealed that PP@miR NPs effectively inhibited subcutaneous tumor progression and achieved partial tumor elimination(2/5),which confirmed the critical role of miR-330-3p in OSCC development.These findings provide a new perspective for the development of OSCC treatments.

关键词： Oral squamous cell carcinoma CircRNA MiRNA sponge Antagomir MiRNA delivery Cisplatin-based nanoparticles Drug delivery systems Tumor elimination