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World Journal of Clinical Cases 2024年第1期12卷 169-175页

作者： Ping-Qiang Qi yi-jun zeng Wei Peng Juan Kuai Department of Neurosurgery The Third Affiliated Hospital of Chengdu Medical College Pidu District People’s HospitalChengdu 611730Sichuan ProvinceChina

BACKGROUND Elizabethkingia miricola is a non-fermenting gram-negative bacterium,which was first isolated from the condensate of the Russian peace space station in *** studies on this bacterium have been carried out in the laboratory,and clinical case studies are *** date,a total of 6 clinical cases have been reported *** SUMMARY We present the first case of postoperative pulmonary infection in a patient with intracerebral hemorrhage due to Elizabethkingia *** imaging character-istics of pulmonary infection were identified and the formulation and selection of the clinical treatment plan for this patient are *** Elizabethkingia miricola infection is *** pulmonary infection occurs,computed tomography imaging may show diffuse distribution of a ground glass density shadow in both lungs,the air containing bronchial sign in local areas,thickening of bronchial vascular bundle,and pleural effusion.

关键词： Elizabethkingia miricola Cerebral hemorrhage surgery Postoperative pulmonary infection Imaging features Case report

Pollution characteristics and quantitative source apportionment of heavy metals within a zinc smelting site by GIS-based PMF and APCS-MLR models

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Journal of Environmental Sciences 2024年第10期144卷 100-112页

作者： Huagang Lv Zhihuang Lu Guangxuan Fu Sifang Lv jun Jiang yi Xie Xinghua Luo Jiaqing zeng Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Zhuzhou Qingshuitang Technology Co. Ltd.Zhuzhou 412000China New World Environment Protection Group of Hunan Changsha 410083China

The abandoned smelters present a substantial pollution threat to the nearby soil and *** this study,63 surface soil samples were collected from a zinc smelter to quantitatively describe the pollution characteristics,ecological risks,and source apportionment of heavy metal(loid)s(HMs).The results revealed that the average contents of Zn,Cd,Pb,As,and Hg were 0.4,12.2,3.3,5.3,and 12.7 times higher than the risk screening values of the construction sites,***,the smelter was accumulated heavily with Cd and Hg,and the contribution of Cd(0.38)and Hg(0.53)to ecological risk was 91.58%.ZZ3 and ZZ7 were the most polluted workshops,accounting for 25.7%and 35.0%of the pollution load and ecological risk,*** influence of soil parent materials on pollution was minor compared to various workshops within the *** with PMF,APCS-MLR and GIS analysis,four sources of HMs were identified:P1(25.5%)and A3(18.4%)were atmospheric deposition from the electric defogging workshop and surface runoff from the smelter;P2(32.7%)and A2(20.9%)were surface runoff of As-Pb foul acid;P3(14.5%)and A4(49.8%)were atmospheric deposition from the leach slag drying workshop;P4(27.3%)and A1(10.8%)were the smelting process of zinc *** paper described the distribution characteristics and specific sources of HMs in different process workshops,providing a new perspective for the precise remediation of the smelter by determining the priority control factors.

关键词： Smelter site Heavy metal(loid)s Source apportionment Positive matrix factorization Absolute principal component score-multiple linear regression

Effect of micro-Al_(2)O_(3) powders on oxidation and corrosion behaviors of low-carbon MgO-C refractories

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Journal of Iron and Steel Research International 2024年第6期31卷 1522-1534页

作者： Yang Chen zeng-yi Li Hao-bo Tan Yu-ran Fu jun Ding Cheng-ji Deng Chao Yu School of Materials Science and Engineering Hunan Institute of TechnologyHengyang 421002HunanChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

To solve the problem of poor high-temperature service performance caused by low carbonization of MgO-C refractories,low-carbon MgO–C refractories with excellent thermal shock,oxidation and corrosion resistances were successfully designed by using SiC whiskers as reinforcing phases and introducing micro-Al_(2)O_(3) powders as *** results indicated that the addition of micro-Al_(2)O_(3) powders optimized the internal structure of the material,like the columnar β-Si_(3)N_(4) with a stepped distribution and the mosaic structure formed between granular and flaky Mg_(2)SiO_(4),which synergistically strengthened and toughened the material and gave the material excellent mechanical properties and thermal shock ***,the cold modulus of rupture and cold crushing strength after thermal shock were increased by 4.1 and 20.3 MPa,***,the addition of micro-Al_(2)O_(3) powders promoted the formation of fine particles of Mg_(2)SiO_(4),MgAl_(2)O_(4) and MgO,as well as a dense protective layer of Mg_(2)SiO_(4) in the material under high-temperature ***,spinel and high-temperature solid solution were formed in the corrosion *** oxidation and corrosion resistances were greatly improved by 41%and 15%,respectively.

关键词： Low-carbon MgO-C refractory Oxidation resistance Corrosion resistance Thermal shock resistance Micro-Al_(2)O_(3)powder

Exploring the mechanisms of calcium carbonate deposition on various substrates with implications for effective anti-scaling material selection

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Petroleum Science 2024年第4期21卷 2870-2880页

作者： Lu Gong Fei-yi Wu Ming-Fei Pan jun Huang Hao Zhang Jing-Li Luo Hong-Bo zeng College of Science China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum Basic Research Center for Energy Interdisciplinary College of Science China University of Petroleum Department of Chemical and Materials Engineering University of Alberta Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Ministry of Education) School of Mechanical Engineering Shandong University

The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging. It is of practical and fundamental importance to understand the scaling mechanisms and develop efficient anti-scaling strategies. However,the underlying surface interaction mechanisms of scalants(e.g., calcite) with various substrates are still not fully understood. In this work, the colloidal probe atomic force microscopy(AFM) technique has been applied to directly quantify the surface forces between calcite particles and different metallic substrates,including carbon steel(CR1018), low alloy steel(4140), stainless steel(SS304) and tungsten carbide,under different water chemistries(i.e., salinity and p H). Measured force profiles revealed that the attractive van der Waals(VDW) interaction contributed to the attachment of the calcium carbonate particles on substrate surfaces, while the repulsive electric double layer(EDL) interactions could inhibit the attachment behaviors. High salinity and acidic p H conditions of aqueous solutions could weaken the EDL repulsion and promote the attachment behavior. The adhesion of calcite particles with CR1018 and4140 substrates was much stronger than that with SS304 and tungsten carbide substrates. The bulk scaling tests in aqueous solutions from an industrial oil production process showed that much more severe scaling behaviors of calcite was detected on CR1018 and 4140 than those on SS304 and tungsten carbide, which agreed with surface force measurement results. Besides, high salinity and acidic p H can significantly enhance the scaling phenomena. This work provides fundamental insights into the scaling mechanisms of calcite at the nanoscale with practical implications for the selection of suitable antiscaling materials in petroleum industries.

关键词： Scaling phenomenon Metallic substrates Surface forces Bulk scaling tests

The critical role of energetic fluctuations in charge separation for efficient molecular doping of organic semiconductors

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Science China Chemistry 2024年第11期67卷 3675-3680页

作者： Yan zeng Guangchao Han Yuanping yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Molecular doping is essential to improve the electrical conductivity of organic semiconductors for high-performance organic electronic devices. However, the doping efficiency is influenced by several factors, such as the energy levels, energetic fluctuations, dielectric properties, and molecular packing structures of the doped films, and the underlying mechanisms for highefficiency doping are still unclear. Here, through multi-level theoretical simulations on a series of fullerene derivatives, we identify that the energetic fluctuations can play a decisive role in activating charge separation for molecular doping. In particular,the doping efficiency appears to be exponentially increased with the fluctuation of charge polarization energies. Therefore,although the charge mobility is somewhat decreased, the experimental electrical conductivity is improved with the increased energetic fluctuation. Moreover, it has been found that polarization energy fluctuation can be effectively enhanced by simply introducing side chains with greater flexibility into organic semiconductors. This article paves the way towards high-efficiency molecular doping of organic semiconductors.

关键词： doping efficiency polarization energies energetic fluctuations organic semiconductors

Developing and validating a predictive model of delivering large-forgestational-age infants among women with gestational diabetes mellitus

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World Journal of Diabetes 2024年第6期15卷 1242-1253页

作者： yi-Tian Zhu Lan-Lan Xiang Ya-jun Chen Tian-ying Zhong jun-jun Wang Yu zeng Department of Clinical Laboratory Jinling Clinical Medical College of Nanjing Medical UniversityNanjing 210002Jiangsu ProvinceChina Department of Clinical Laboratory Women’s Hospital of Nanjing Medical UniversityNanjing Women and Children’s Healthcare HospitalNanjing 210003Jiangsu ProvinceChina

BACKGROUND The birth of large-for-gestational-age(LGA)infants is associated with many shortterm adverse pregnancy *** has been observed that the proportion of LGA infants born to pregnant women with gestational diabetes mellitus(GDM)is significantly higher than that born to healthy pregnant ***,traditional methods for the diagnosis of LGA have ***,this study aims to establish a predictive model that can effectively identify women with GDM who are at risk of delivering LGA *** To develop and validate a nomogram prediction model of delivering LGA infants among pregnant women with GDM,and provide strategies for the effective prevention and timely intervention of *** The multivariable prediction model was developed by carrying out the following ***,the variables that were associated with LGA risk in pregnant women with GDM were screened by univariate analyses,for which the P value was<***,Least Absolute Shrinkage and Selection Operator regression was fit using ten cross-validations,and the optimal combination factors were se-lected by choosing lambda 1se as the *** final predictors were deter-mined by multiple backward stepwise logistic regression analysis,in which only the independent variables were associated with LGA risk,with a P value<***,a risk prediction model was established and subsequently evaluated by using area under the receiver operating characteristic curve,calibration curve and decision curve *** After using a multistep screening method,we establish a predictive *** risk factors for delivering an LGA infant were identified(P<0.01),including weight gain during pregnancy,parity,triglyceride-glucose index,free tetraiodothyronine level,abdominal circumference,alanine transaminase-aspartate aminotransferase ratio and weight at 24 gestational *** nomogram’s prediction ability was supported by the area under the curve(0.703,0.709,and 0.699 f

关键词： Large-for-gestational-age Gestational diabetes mellitus Predictive model Nomogram Triglyceride-glucose index

Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： Tianqi WANG Liu LIU jun LI Lifang zeng School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and *** wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance ***,the time-history performance is equally important in the design of motion mechanism and flight control *** this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing ***,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics *** aerodynamic surrogate model for flapping wing is obtained after the convergence of *** surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and ***,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the ***,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged *** the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried *** final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

Mass transfer in heap leaching of weathered crust elution deposited rare earth ore with Al_(2)(SO_(4))_(3) solution

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Journal of Rare Earths 2024年第6期42卷 1175-1181,I0007页

作者： Jingqun yin Dedong zeng jun Tian Yaqing Weng Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang330096China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang330031China

In order to increase efficiency and avoid NH^(4+)-N pollution in the leaching process of weathered crust elution-deposited rare earth ores,the mass transfer in heap leaching with Al_(2)(SO_(4))_(3) solution was simulated with column elution and experimentally *** results indicate that the leaching yield is also up to 99%for leaching with aluminum sulfate instead of ammonium *** optimal flow rate is 60 mL/h,the height equivalent to a theoretical plate(HETP)is 1.29 mm *** peak value position of RE^(3+)is 60 mL/h,Fe^(3+)is 100 mL/h,however,Al^(3+)is 150 mL/h,and the heap leaching process has kinetic separation effect.

关键词： Raree arths Mass transfer Process optimization Heapleaching Weathered crust elution-deposited rare earth ore

Minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal shunt

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第4期12卷 293-297页

作者： Lu JIA Zhong-xin ZHAO Chao YOU Jia-gang LIU Si-qing HUANG Min HE Pei-gang JI Jie DUAN yi-jun zeng Guo-ping LI Department of Neurosurgery West China Hospital of Sichuan University Chengdu 610041 China Department of Neurosurgery Dujiangyan Renmin Hospital of Sichuan Province Dujiangyan 611830 China

Objective:To investigate the clinical value of a minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal (LP) ***:The clinical and long-term follow-up data of 256 patients suffering from communicating hydrocephalus and undergoing percutaneous LP shunt during 1998 to 2008 were retrospectively ***:After the follow-up,which lasted 6 months to 10 years,219 cases of communicating hydrocephalus recovered well (ventricular size returned to normal and symptoms completely disappeared),25 cases were brought under control (ventricle size reduced by 50% and symptoms partially abated),and 12 cases showed no obvious *** obese subjects needed modifications of the shunt due to the obstruction of the abdominal end following wrapping,and one subject underwent extubation as the subject was unable to tolerate stimulation of the cauda *** effectiveness of shunting was 91.40% and the probability of shunt-tube obstruction,which occurs predominantly in the abdominal end,was only 5.85%,far lower than that of ventriculoperitoneal (VP) *** subjects had a history of infection following VP ***:LP shunting is minimally invasive and effective in treating communicating hydrocephalus,with fewer complications.

关键词： Communicating hydrocephalus Percutaneous lumboperitoneal shunt Cerebrospinal fluid

Thermal conductivity of iron under the Earth’s inner core pressure

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Chinese Physics B 2024年第10期33卷 343-348页

作者： Cui-E Hu Mu-Xin Jiao Xue-Nan Yang Zhao-yi zeng jun Chen College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 400047China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Center for Applied Physics and Technology Peking UniversityBeijing 100071China

The thermal conductivity ofε-iron at high pressure and high temperature is a key parameter to constrain the dynamics and thermal evolution of the Earth’s *** this work,we use first-principles calculations to study the Hugoniot sound velocity and the thermal transport properties ofε-*** total thermal conductivity considering lattice vibration is 200 W/mK at the Earth’s inner core *** suppressed anharmonic interactions can significantly enhance the lattice thermal conductivity under high pressure,and the contribution of the lattice thermal conductivity should not be ignored under the Earth’s core conditions.

关键词： thermal conductivity first-principles high pressure and high temperature