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Loading capacity and emulsification phenomena of HREE extraction by dialkylphosphinic acids with different β,γ,δ-substituents

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Journal of Rare Earths 2024年第1期42卷 191-199,I0007页

作者： Junlian Wang Guodong Xu Wen Xu Jianguo Cui Yufu chen Ziyong chang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines Beijing100083China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou014030China

The relationship between dialkylphosphinic acid structure and their loading capacity for HREEs and emulsification phenomena has rarely been *** this paper,we took Lu extraction as an example to study the effect of β,γ,δ-substituents of dialkylphosphinic acids on their loading capacity and anti-emulsification performance for *** discuss conveniently,the dialkylphosphinic acids were classified into two groups:β-substituent group(P208,INET-1,P218,USTB-1 and P227)and γ,δ-substituent group(P218,P2132 and Cyanex 272).For β-substituent group extractants,their loading capacities are in the order P208(299.7 mg/L)≈INET-1(299.5 mg/L)>P218(270.8 mg/L)>>USTB-1(163.1 mg/L)>P227(151.4 mg/L),while their anti-emulsification/gelation performances are just in the opposite order P227>USTB-1>P218>P208≈INET-1 under the studied *** γ,δ-substituent group extractants,their loading capacities are in the order P218(270.8 mg/L)>P2132(192.3 mg/L)>Cyanex272(131.7 mg/L),while the anti-emulsification performance of P218 is better than those of P2132 and Cyanex *** loading capacity data given in the parentheses are obtained through repeatedly extracting Lu from ~4×10^(-4)mol/L of Lu aqueous feed solution with initial pH of 2.40 by 0.01 mol/L extractant at phase ratio A/O of 1:1.

关键词： Heavy rare earth element Dialkylphosphinic acid Extraction Loading capacity Emulsification

Response of phytoplankton functional group to spring drought in a large subtropical reservoir

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Journal of Oceanology and Limnology 2024年第5期42卷 1586-1596页

作者： Yue WU Qi YE Siwen chen Kaining chen Shuzhan MA Yiheng chang Xiaoli SHI State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in the Middle and Lower Reaches of Yangtze River Jiangsu Provincial Academy of Environmental ScienceNanjing 210036China

Global warming has caused an increase in the frequency and duration of droughts *** could trigger large changes in physico-chemical conditions and phytoplankton community in waterbodies,resulting in a shift in the phytoplankton *** diatom blooms in reservoirs have been increasingly observed in the past decade in the Taihu Lake *** aim of the present study is to elucidate the impacts of droughts on aquatic environment and to determine the driving factors for the succession of the phytoplankton functional groups based on the analysis of data collected during spring from 2009 to 2020 in the Daxi *** unimodal relationship between 1-month aggregated precipitation index and phytoplankton species richness indicated the competitive exclusion occurred in extremely drought *** structural equation modeling indicated that drought-related low water level conditions intensified sediment resuspension,and increased the phosphorus-enriched nonalgal turbidity in the Daxi ***,a steady shift in the Reynolds phytoplankton functional groups from L 0,TD,J,X 2,and A(phytoplankton taxa preferring low turbidity and nutrient conditions)to TB(pennate diatoms being adapt to turbid and nutrient-rich conditions)was *** increased TP and non-algal turbidity in addition to the lowered disturbance contribute to the prevalence of Group *** the difficulties in nutrient control,timely water replenishment is often a feasible method of controlling the dominance of harmful algae for reservoir ***,alternative water sources are in high demand for ensuring ecological safety and water availability when dealing with drought.

关键词： drought reservoir sediments resuspension phytoplankton functional group diatom

对基于行的文字图像光照平衡方法之改进(英文)

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应用科学学报 2008年第5期26卷 499-505页

作者：张真诚陈志豪林珮瑜国立中正大学资讯工程学系逢甲大学资讯工程学系

用数字相机拍摄时,不恰当的光源常导致图像中的不均匀光照,用扫描仪获取图像时也有同样问题.不规则照明对图像质量造成严重损害,用光照平衡技术可消除图像中的这种不均匀照明.该文针对文字图像提出一种光照平衡的改进方法,利用对比度加... 详细信息

用数字相机拍摄时,不恰当的光源常导致图像中的不均匀光照,用扫描仪获取图像时也有同样问题.不规则照明对图像质量造成严重损害,用光照平衡技术可消除图像中的这种不均匀照明.该文针对文字图像提出一种光照平衡的改进方法,利用对比度加权来扩大文字和背景之间的差异,使直方图更为均衡,降低不成比例的光强分布引起的对比度不均匀性.实验结果表明,新方法可有效改进失真文字图像的质量,提高文档的可读性.

关键词：光照平衡照度数字化对比度增强

Lubrication condition monitoring of journal bearings in diesel engine based on thermoelectricity

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Friction 2024年第11期12卷 2532-2547页

作者： Yuhao LV Hao LIU Zhigang chen Weijie chang Hui ZHANG Hulin LI Shanghai Jiao Tong University Shanghai 200240China National Key Laboratory of Marine Engine Science and Technology Shanghai 201108China Shanghai Marine Diesel Engine Research Institute Shanghai 201108China Hunan Aviation Powerplant Research Institute Aero Engine Corporation of ChinaHunan 412002China

There is still a lack of effective lubrication condition monitoring methods in the field of diesel *** paper proposes a novel thermoelectric approach to divide the lubrication state of ***,the generation mechanism of thermoelectric potential on bearings is ***,both experimental and simulation studies are done,and a strong correlation between lubrication and thermoelectric potential is *** film thickness and temperature are further confirmed as significant factors influencing thermoelectric ***,the thermoelectric potential increases with ***,a small film thickness ratio(when the film thickness ratio is less than 4)will suppress the thermoelectric *** typical lubrication states of bearings are distinguished through thermoelectric potential and supported by the Stribeck curve ***,the significant influence of lubrication on the bearing is confirmed through the analysis of surface morphology and composition.

关键词： journal bearing lubrication state,thermoelectric potential condition monitoring

A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： chang Liu Yan-Jun Wu Jing-Zheng Wu chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

Intelligent gold nanocluster for effective treatment of malignant tumor via tumor-specific photothermal–chemodynamic therapy with AIE guidance

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National Science Review 2024年第5期11卷 326-342页

作者： Feng Liu Tianfeng Yang Xiaowei chang Li chen cheng cheng Xiuhong Peng Haihu Liu Yanmin Zhang Xin chen School of Energy and Power Engineering Xi'an Jiaotong University Department of Chemical Engineering Shaanxi Key Laboratory of Energy Chemical Process IntensificationInstitute of Polymer Science in Chemical Engineering School of Chemical Engineering and Technology Xi'an Jiaotong University School of Pharmacy Health Science Center Xi'an Jiaotong University

Precise and efficient therapy of malignant tumors is always a challenge. Herein, gold nanoclusters co-modified by aggregation-induced-emission（AIE） molecules, copper ion chelator（acylthiourea） and tumor-targeting agent（folic acid） were fabricated to perform AIE-guided and tumor-specific synergistic therapy with great spatio-temporal controllability for the targeted elimination and metastasis inhibition of malignant tumors. During therapy, the functional gold nanoclusters（Au NTF） would rapidly accumulate in the tumor tissue due to the enhanced permeability and retention effect as well as folic acid-mediated tumor targeting, which was followed by endocytosis by tumor cells. After that, the overexpressed copper ions in the tumor cells would trigger the aggregation of these intracellular Au NTF via a chelation process that not only generated the photothermal agent in situ to perform the tumor-specific photothermal therapy damaging the primary tumor, but also led to the copper deficiency of tumor cells to inhibit its ***, the copper ions were reduced to cuprous ions along with the chelation, which further catalysed the excess H2O2in the tumor cells to produce cytotoxic reactive oxygen species, resulting in additional chemodynamic therapy for enhanced antitumor efficiency. The aggregation of Au NTF also activated the AIE molecules to present fluorescence, which not only imaged the therapeutic area for real-time monitoring of this tumor-specific synergistic therapy, but also allowed us to perform near-infrared radiation at the correct time point and location to achieve optimal photothermal therapy. Both in vitro and in vivo results revealed the strong tumor elimination, effective metastasis inhibition and high survival rate of tumor-bearing mice after treatment using the Au NTF nanoclusters, indicating that this AIE-guided and tumor-specific synergistic strategy could offer a promising approach for tumor therapy.

关键词： AIE-guided precise tumor treatment copper-dependent photothermal therapy copper-triggered chemodynamic therapy primary tumor elimination copper-plunder-induced metastasis inhibition

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

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Petroleum Science 2024年第2期21卷 1171-1189页

作者： Kun-Peng Zhang Mian chen chang-Jun Zhao Su Wang Yong-Dong Fan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering in china University of Petroleum Beijing102249China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment ***, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,china,since the Late Pleistocene

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Journal of Oceanology and Limnology 2024年第3期42卷 772-786页

作者： Dongqin HUANG Xiaolong LI Zilong LI Pei Sun LOH Jianxiong HU Jianfang chen Yuan-Pin chang chin-Wen YANG Qin GAO Institute of Marine Geology and Resources Ocean CollegeZhejiang UniversityZhoushan 316021China Ministry of Water Resources of the People’s Republic of china Beijing 100054China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Department of Oceanography Sun Yat-sen UniversityKaohsiung 80424China

A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East china was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the changjiang(Yangtze)*** lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin *** increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late ***,a time lag effect of temperature on vegetation abundance was also *** relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this *** results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change.

关键词： Yongjiang River estuary sedimentary organic matter lignin environmental change Late Pleistocene

Clinical application of eight-zone laparoscopic dissection strategy for rectal cancer:Experience and discussion

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World Journal of Gastroenterology 2024年第30期30卷 3574-3583页

作者： chang chen Xiang Zhang Xin Li Yan-Lei Wang Department of General Surgery Rongchang People's HospitalChongqing 250012China Department of Colorectal Surgery Qilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina Department of General Surgery Huantai Branch of Qilu Hospital of Shandong UniversityZibo 255000Shandong ProvinceChina

BACKGROUND The incidence of rectal cancer is increasing worldwide,and surgery remains the primary treatment *** the advent of total mesorectal excision(TME)technique,the probability of tumor recurrence post-surgery has significantly ***'focus has gradually shifted towards minimizing the impact of surgery on urinary and sexual *** these concerns,the optimal dissection of the rectal lateral ligaments and preservation of the pelvic floor neuro-vascular bundle have become *** explore the optimal surgical technique for TME and establish a standardized surgical protocol to minimize the impact on urinary and sexual functions,we propose the eight-zone dissection strategy for pelvic floor *** To compare the differences in surgical specimen integrity and postoperative quality of life satisfaction between the traditional pelvic floor dissection strategy and the innovative eight-zone dissection *** We analyzed the perioperative data of patients who underwent laparoscopic radical resection of rectal cancer at Qilu Hospital of Shandong University between January 1,2021 and December 1,*** study included a total of 218 patients undergoing laparoscopic radical surgery for rectal cancer,among whom 109 patients underwent traditional pelvic floor dissection strategy,and 109 patients received the eight-zone dissection *** There were no significant differences in general characteristics between the two *** in the eight-zone dissection group had higher postoperative specimen integrity(88.1%vs 78.0%,P=0.047).At the 3-month followup,patients in the eight-zone surgery group had better scores in urinary issues(6.8±3.3 vs 5.3±2.5,P=0.045)and male sexual desire(2.2±0.6 vs 2.5±0.5,P=0.047)compared to the traditional surgery strategy *** This study demonstrates that the eight-zone dissection strategy for laparoscopic lateral ligament dissection of rectal cancer is safe and ***

关键词： Eight-zone dissection strategy Rectal cancer Lateral ligament dissection Nerve injury Total mesorectal excision surgery