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Simultaneous detection of flare-associated kink oscillations and extreme-ultraviolet waves

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Science China(Technological Sciences) 2024年第5期67卷 1592-1601页

作者： LI dong HOU ZhenYong BAI XianYong LI Chuan fang Matthew ZHAO HaiSheng WANG JinCheng NING ZongJun Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210023China Yunnan Key Laboratory of the Solar Physics and Space Science Kunming650216China School of Earth and Space Sciences Peking UniversityBeijing100871China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing100049China School of Astronomy and Space Science Nanjing UniversityNanjing210023China Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing210023China Columbus Academy GahannaOhio43230USA Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China Yunnan Observatories Chinese Academy of SciencesKunming650216China

Kink oscillations,which are frequently observed in coronal loops and prominences,are often accompanied by extreme-ultraviolet(EUV)***,much more needs to be explored regarding the causal relationships between kink oscillations and EUV *** this article,we report the simultaneous detection of kink oscillations and EUV waves that are both associated with an X2.1 flare on 2023 March 03(SOL2023-03-03T17:39).The kink oscillations,which are almost perpendicular to the axes of loop-like structures,are observed in three coronal loops and one *** short loop shows in-phase oscillation within the same period of 5.2 min at three *** oscillation could be triggered by the pushing of an expanding loop and interpreted as the standing kink *** lags are found between the kink oscillations of the short loop and two long loops,suggesting that the kink wave travels in different *** kink oscillations of one long loop and the prominence are possibly driven by the disturbance of the coronal mass ejection(CME),and that of another long loop might be attributed to the interaction of the EUV *** onset time of the kink oscillation of the short loop is nearly same as the beginning of an EUV *** fact demonstrates that they are almost *** EUV wave is most likely excited by the expanding loop structure and shows two *** leading component is a fast coronal wave,and the trailing one could be due to the stretching magnetic field lines.

关键词： coronal loops solar flares solar prominence solar oscillations extreme-ultraviolet wave magnetohydrodynamic

Strategies to advance thermoelectric performance of PbSe and PbS materials

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Rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian Qiu-Juan Cui Shu-fang Wang Li-dong Zhao Shijiazhuang Key Laboratory of Low Carbon Energy Materials College of Chemical EngineeringShijiazhuang UniversityShijiazhuang 050035China Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa,making them promising for waste heat recovery and efficient cooling ***,extensively investigated thermoelectric materials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***,the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's *** the past few years,researchers have shown increasing interest in PbSe-and PbS-based materials,primarily attributed to their abundant elemental supply and relatively low *** assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric *** strategies include optimizing carrier concentration(aliovalent doping,dynamic doping and defect state),enhancing density-of-state effective mass(band convergence,band flattening and energy filtering effect),optimizing carrier mobility(band sharpening and band alignment)and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing).This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.

关键词： PbSe and PbS thermoelectric materials Carrier concentration Density-of-state effective mass Carrier mobility Lattice thermal conductivity

Thermal stability improvement and microstructure optimization of high cobalt content Nd-Fe-B magnets via terbium grain boundary diffusion

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Journal of Rare Earths 2024年第8期42卷 1531-1538,I0004页

作者： Jiyuan Xu Ruiyang Meng Jing Liu Jiateng Zhang Rui Han Yikun fang Shengzhi dong Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China

The substitution of Fe by Co in the 2:14:1 phase is an effective method to increase the Curie temperature and enhance the thermal stability of the Nd-Fe-B ***,the accumulation of Co ele ment at the grain boundaries(GBs) changes the GBs from nonmagnetic to ferromagnetic and causes the thinlayer GBs to become rare,In this paper,the method of diffusing Tb element was chosen to improve the microstructure and temperature stability of high-Co *** original sintered Nd_(28.5)Dy_(3)-CO_(x)e_(bal)M_(0.6)B_(i)(x=0,6 wt%,12 wt%;M = Cu,Al,Zr) magnets with different Co contents were diffused with Tb by grain boundary diffusion(GBD).After GBD,high-Co magnets exhibit more continuously distributed thin-layer GBs,and their thermal stability is significantly *** high-Co magnets(x=6 wt%),the absolute value of the temperature coefficient of coercivity decreases from 0.603%/K to0.508%/K in the temperature range of 293-413 K,that of remanence decreases from 0.099%/K to 0.091%/K,and the coercivity increases from 18.44 to 25.04 *** electron microscopy(TEM)characterization reveals that there are both the 1:2 phase and the amorphous phase in the high-Co magnet before and after GBD,EDS elemental analysis shows that Tb element is more likely to preferentially replace the rare earth elements in the 2:14:1 main phase than in the 1:2 phase and the amorphous *** concentration of Tb at the edge of the main phase is much higher than that in the 1:2phase and amorphous phase,which is beneficial to the improvement of the *** preferential replacement of Tb elements at the edge of the 2:14:1 phase and thin-layer GBs with a more continuous distribution are synergistically responsible for improving the thermal stability of high-Co *** study indicates that GBD is an effective method to improve the microstructure and thermal stability of high-Co magnets.

关键词： Nd-Fe-B magnets Coercivity Grain boundary diffusion Thermal stability Micro structure Rare earths

Effects of Biochar Inoculation with Bacillus megaterium on Rice Soil Phosphorus Fraction Transformation and Bacterial Community Dynamics

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Rice science 2024年第4期31卷 361-365,I0001-I0003页

作者： YU Keru xue Zhaokun fang Xianzhi MA Jiawei WANG Yongjun LIU Dan YE Zhengqian State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province Zhejiang A&F UniversityHangzhou 311300China Department of Forest Protection College of Forestry and BiotechnologyZhejiang A&F UniversityHangzhou 311300China

Rice husk biochar inoculated with Bacillus megaterium(BM)(referred to as BM-inoculated biochar, BMB) and uninoculated rice husk biochar(RHB) were added to soil at two rates(0.5%, as BMB1 and RHB1, respectively, and 1.0%, as BMB2 and RHB2, respectively) in an incubation experiment to comprehensively evaluate their effects on basic soil properties, phosphorus(P) fractions, bacterial community composition, and P-cycling genes.

关键词： soil comprehensive Transformation

Age and mean platelet volume-based nomogram for predicting the therapeutic efficacy of metoprolol in Chinese pediatric patients with vasovagal syncope

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World Journal of Pediatrics 2024年第9期20卷 957-965页

作者： Xiao-Juan Du Ya-Qian Huang xue-Ying Li Ying Liao Hong-fang Jin Jun-Bao Du Department of Pediatrics Peking University First HospitalNo.1 Xi’anmen StreetWest DistrictBeijing100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityNo.38Xueyuan RoadHaidian DistrictBeijing100191China Department of Statistics Peking University First HospitalBeijing100034China

Background Vasovagal syncope(VVS)is the most common type of orthostatic intolerance in *** investigated whether platelet-related factors related to treatment efficacy in children suffering from VVS treated with *** Metoprolol-treated VVS patients were *** median duration of therapy was three *** were followed and divided into two groups,treament-effective group and treatment-ineffective *** and least absolute shrinkage selection operator regressions were used to examine treatment outcome ***-operating characteristic(ROC)curves,precision-recall(PR)curves,calibration plots,and decision curve analyses were used to evaluate the nomogram *** Among the 72 patients who complete the follow-up,treatment-effective group and treatment-ineffective group included 42(58.3%)and 30(41.7%)cases,*** patients in the treatment-effective group exhibited higher mean platelet volume(MPV)[(11.0±1.0)fl vs.(9.8±1.0)fl,P<0.01]and platelet distribution width[12.7%(12.3%,14.3%)vs.11.3%(10.2%,12.2%),P<0.01]than those in the treatment-ineffective *** sex ratio was significantly different(P=0.046).A fit model comprising age[odds ratio(OR)=0.766,95%confidence interval(CI)=0.594-0.987]and MPV(OR=5.613,95%CI=2.297-13.711)might predict therapeutic *** area under the curve of the ROC and PR curves was computed to be 0.85 and 0.9,*** P value of the Hosmer-Lemeshow test was *** decision curve analysis confirmed that managing children with VVS based on the predictive model led to a net advantage ranging from 0.01 to *** nomogram is convenient for clinical *** A novel nomogram based on age and MPV can predict the therapeutic benefits of metoprolol in children with VVS.

关键词： Metoprolol Nomogram Retrospective study Therapeutic effect Vasovagal syncope

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： Qing-Jun Du Hao-Yu Zheng Jian Hou Yong-Ge Liu Jian-fang Sun dong Zhao State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production Research Institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided into 180 equally sized zones based on the CT scanning images, and threedimensional(3D) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. In the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. In the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

Novel magnetic compression technique for the treatment of postoperative anastomotic stenosis in rectal cancer:A case report

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1926-1932页

作者： Miao-Miao Zhang Huan-Chen Sha Hai-Rong xue Yuan-Fa Qin Xiao-Gang Song Yun Li Yu Li Zheng-Wu Deng Yu-Lin Gao fang-fang dong Yi Lyu Xiao-Peng Yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Shaanxi Provincial Key Laboratory of Magnetic Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Gastroenterology The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina

BACKGROUND The treatment of postoperative anastomotic stenosis after excision of rectal cancer is *** balloon dilation and radial incision are not effective in all *** present a new endoscopy-assisted magnetic compression technique(MCT)for the treatment of rectal anastomotic *** successfully applied this MCT to a patient who developed an anastomotic stricture after radical resection of rectal cancer.A 50-year-old man had undergone laparoscopic radical rectal cancer surgery at a local hospital 5 months ago.A colonoscopy performed 2 months ago indicated that the rectal anastomosis was narrow due to which ileostomy closure could not be *** patient came to the Magnetic Surgery Clinic of the First Affiliated Hospital of Xi'an Jiaotong University after learning that we had successfully treated patients with colorectal stenosis using *** performed endoscopy-assisted magnetic compression surgery for rectal *** magnets were removed 16 d later.A follow-up colonoscopy performed after 4 months showed good anastomotic patency,following which,ileostomy closure surgery was *** MCT is a simple,non-invasive technique for the treatment of anastomotic stricture after radical resection of rectal *** technique can be widely used in clinical settings.

关键词： Rectal cancer Magnetic compression technique Magnetosurgery Anastomotic stricture Magnetic surgery clinic Case report

Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7

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Chinese Journal of Integrative Medicine 2024年第6期30卷 543-550页

作者： YU Qian SHU Shi JU Xin-yao PENG Wei REN xue-qi SI Shu-han SONG Shi-zhen XIE xue-yun fang Bang-jiang ZHOU Shuang School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineShanghai201203China College of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China

Objective To observe the angiogenesis effect of electroacupuncture(EA)at Shuigou acupoint(GV 26)in the treatment of cerebral ischemia,and explore the value of miRNA-7(miR-7)in *** First,48 mice were randomly divided into sham operation,middle cerebral artery occlusion(MCAO)model,and EA treatment *** 9 mice were divided into carrier control group,miR-7 knockout group and miR-7 overexpression group(n=3 each group).Finally,20 mice were divided into model and carrier control group,model and miR-7 knockout group,EA treatment and carrier control group and EA treatment and miR-7 overexpression group,with 3–6 mice in each *** MCAO model was established in the MCAO and EA *** deficit score and 2,3,5-triphenyltetrazolium chloride(TTC)staining were used to evaluate the severity of cerebral ***-eosin staining was used to describe basic pathological *** was used to quantify cerebral microvessel ***-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor(KLF4/VEGF)and angiopoietin-2(ANG-2)in the ischemic cerebral *** After EA,neurological deficit scores and infarction volumes decreased,and the density of cerebral microvessels *** the MCAO group,miR-7 expression was higher than that in the sham group(P<0.01).After EA at GV 26,miR-7 expression decreased(P<0.01)and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group(P<0.01).After EA combined with overexpression of miR-7,the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group(P<0.01).After miR-7 knockdown,the expression of KLF4/VEGF and ANG-2 increased(P<0.05 or P<0.01).Conclusions EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEG

关键词： electroacupuncture cerebral ischemia miRNA-7 angiogenesis Shuigou(GV 26) acupuncture points

Advance in reversible Zn anodes promoted by 2D materials

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Rare Metals 2024年第4期43卷 1350-1369页

作者： Shu-Yuan Lei Jin-Xiu Feng Yu-Chao Chen dong Zheng Wen-Xian Liu Wen-Hui Shi fang-fang Wu Xie-Hong Cao School of Materials Science and Engineering Zhejiang University of TechnologyHangzhou310014China Center for Membrane Separation and Water Science and Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

With the growing energy demand associated with high safety and low-cost requirement,aqueous zinc-ion batteries(AZIBs)have been considered as one of the most promising next-generation ***,some key issues,such as uncontrollable dendrites growth,severe corrosion,hydrogen evolution and side reactions of Zn anodes during charge/discharge process,have hindered its pragmatic ***-dimensional(2D)materials hold advantages of unique physical and chemical properties,large surface areas and abundant active sites,which have been successfully used to overcome the above shortcomings of Zn anodes in recent *** this review,the issues and challenges of Zn anodes are ***,the state-of-the-art progress on Zn anodes modification based on 2D materials such as graphene,2D metal carbides and nitrides(MXenes),2D metal-organic frameworks(MOFs),2D covalent organic frameworks(COFs),2D transition metal compounds and other 2D materials is discussed in ***,the perspectives of employing 2D materials in highly reversible Zn anodes are summarized and discussed.

关键词： 2D materials Aqueous zinc-ion battery Zn anodes Dendrites growth