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Synthesis of NiFe_2O_4 Powders Well Defined in Size and Morphologies

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Chinese Chemical Letters 2002年第4期13卷 389-392页

作者： Yu Ting ZHAO De Hong CHEN Dai Rong CHEN xiu ling jiao Department of Chemistry Shandong UniversityJinan 250100

The uniform NiFe2O4 powders with different particle size and morphologies (octahedral, cubic and spherical) have been prepared from different precursors via hydrothermal process. The nanocrystallines derived from pre... 详细信息

关键词： Nickel ferrite hydrothermal method superparamagnetism.

Synthesis of Monodisperse α-Fe_2O_3 Particles in Short Periods

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Chinese Chemical Letters 2003年第3期14卷 323-326页

作者： Yu Ting ZHAO De Hong CHEN Dai Rong CHEN xiu ling jiao Department of Chemistry Shandong UniversityJinan 250100

Monodisperse a-Fe2O3 particles with different particle size (ca. 62010 nm or 604 nm) have been successfully prepared by hydrothermal method in short periods. In this process, the crystal-growing inhibitor (DBS) favor... 详细信息

关键词： Hematite hydrothermal method monodisperse particles.

Synthesis and Structure of Vanadium-barium Complex of 2,4,6-Tripicolinato with 20-Member Macrocyclic Cavities

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Chinese Chemical Letters 2003年第7期14卷 740-743页

作者： Yu Xia DIAO Yang TIAN Si Hui ZHAN Wen Xing ZHANG xiu ling jiao Dai Rong CHEN School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100

A new heteronuclear complex, dimer [(2-OH2)2Ba2(H2O)4][VO2(tpa)]24H2O (tpa: 2,4,6-tripicolinate trianion), was synthesized and structurally determined by X-ray diffraction technique where all hydrogen atoms have been located directly. The coordination geometry of V(V) ion is a distorted trigonal bipyrimid and that of Ba(II) ion is a capped square antiprism. One 2-O bridging bond and two hydrogen bonds act between the coordination geometries. A 1-D extended porous construction containing 20-member cavities is observed in the crystal.

关键词： Heteronuclear vanadium-barium complex synthesis cavity structure.

STUOIES　ON　TRANSITION　METAL　COMPLEXES　OF　SCHIFF　BASE—OXYGEN—CARRYING　PROPERTIES　OF　THREE　COBALT（Ⅱ）　COMPLEXES　OF　N－SALICYLIDENEAMINO　ACIDS

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Chinese Chemical Letters 1994年第1期5卷 55-58页

作者： Xiao Yan LI Hong Jian SUN Xue Gui CUl De Xin LIU xiu ling jiao (Department of Chemistry, Shandoug University, Jiuan, 250100)

The syntheses of three cobalt(Ⅱ) complexes of tridentate Schiff bases and their dioxygen affinities in different solvents are reported. The complexes are N-salicylidene-L-alanine dihydrated cobalt(Ⅱ) (CoSAAL (H2O)2), N-salicylidene-L-leucine monohydrated cobalt (Ⅱ) (CoSALL(H2O)) and N-salicylidene-L-phenylalanine dihydrated cobalt(Ⅱ) (CoSALPHENA(H2O)2). The solents employed are pyridine (Py) anddimethylformamide (DMF).

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Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality

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Petroleum Science 2024年第3期21卷 2139-2153页

作者： Zhen-Hua Zhang Dan ling Qin-Xin Yang Yan-Chao Feng Jing xiu School of Economics Lanzhou UniversityLanzhou 730000GansuChina Institute of Green Finance Lanzhou UniversityLanzhou 730000GansuChina School of Management Lanzhou UniversityLanzhou 730000GansuChina School of Business Zhengzhou UniversityZhengzhou 450001HenanChina Institute of Economics Jilin Academy of Social SciencesChangchun130033JilinChina

Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction *** study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each *** research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI *** the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary ***,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy *** study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy.

关键词： Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction

Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

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Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao Hao Zhao Shuo-Fei Dong Qi Guo jiao-jiao Xie Mei-ling Lv Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric *** this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample *** compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also *** results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest *** actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward *** was the main exposure pathway for REEs in PM_(2.5)for both children and *** contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and *** exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great *** was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report

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World Journal of Clinical Cases 2024年第5期12卷 1010-1017页

作者： jiao Yang Xin-ling Li Qing-Bing Li Department of Rehabilitation Medicine Center West China HospitalChengdu 610041Sichuan ProvinceChina Key Laboratory of Rehabilitation Medicine in Sichuan Province West China HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive ***,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound *** study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower *** examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root ***,the patient was diagnosed with *** patient was treated with a novel ultrasound-guided LRB *** patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month *** This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane *** studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS.

关键词： Lateral recess stenosis Ultrasound Lateral recess block Real-time visualization Low back pain Case report

Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan xiu-Fang Li Meng-Ya Guo Mei Chen Ming Lv Rui Li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons

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Biomedical and Environmental Sciences 2024年第5期37卷 479-493页

作者： LI Yang LIN Dan ZHANG xiu Qin JU Guang xiu SU Ya ZHANG Qian DUAN Hai Ping YU Wei Sen WANG Bing ling PANG Shu Tao Department of Epidemiology and Health Statistics School of Public HealthQingdao UniversityQingdao 266021ShandongChina Department of Environmental Health Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Physicochemical Laboratory Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Section of Child Health Care Huangdao Maternity and Child Health Care Hospital of QingdaoQingdao 266499ShandongChina Qingdao Blood Center Qingdao 266071ShandongChina

Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal *** Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old ***,37 children were categorized into low-and high-exposure groups based on the sum of the ten ***-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine ***,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina *** The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide ***,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in *** Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived *** investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes.

关键词： Child Gut microbiota Non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile