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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong ZHANG Jingying ZUO Xin LI jiang qin Wen BAO School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

Impedance Model for Instability Analysis of LCC-HVDCs Considering Transformer Saturation

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1309-1319页

作者： qin jiang Ruiting Xu Baohong Li Xiang Chen Yue Yin Tianqi Liu Frede Blaabjerg College of Electrical Engineering Sichuan UniversityChengdu 610065China Smart Grid Key Laboratory of Sichuan Province Chengdu 610065China Department of Energy Technology Aalborg UniversityAalborg 9920Denmark

In line commutated converter based high-voltage direct current(LCC-HVDC)transmission systems,the trans-former saturation can induce harmonic instability,which poses a serious threat to the safe operation of the power ***-ever,the nonlinear characteristics of the power grids introduced by the transformer saturation considerably limit the application of the conventional analysis *** address the issue,this paper derives a linear model for the transformer saturation caused by the DC current due to the converter ***-terwards,the nonlinear characteristics of power grids with the transformer saturation is described by a complex valued imped-ance *** on the derived impedance matrix,the sys-tem harmonic stability is analyzed and the mechanism of the transformer saturation induced harmonic instability is ***,the sensitivity analysis is conducted to find the key fac-tors that influence the system core saturation *** proposed impedance model is verified by the electromagnetic transient simulation,and the simulation results corroborate the effectiveness of the proposed impedance *** TermsLine commutated converter based high voltage direct current(LCC-HVDC),transformer saturation,harmonic instability,impedance model.

关键词： Line commutated converter based high voltage direct current(LCC-HVDC) transformer saturation harmonic instability impedance model

Problem-solving model guided by stimulus-organism-response theory:State of mind and coping styles of depressed mothers after cesarean delivery

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World Journal of Psychiatry 2024年第6期14卷 945-953页

作者： Rui-Fang Yuan Mei-qin jiang Juan Li Jing-Jing Zhang Department of Gynecology and Obstetrics Jiangyin People's HospitalJiangyin 214400Jiangsu ProvinceChina Department of Gynecology The Fifth People's Hospital of WuxiWuxi 214000Jiangsu ProvinceChina Obstetrics and Gynecology Ward II Jiangnan University Affiliated HospitalWuxi 214131Jiangsu ProvinceChina

BACKGROUND The use of a problem-solving model guided by stimulus-organism-response(SOR)theory for women with postpartum depression after cesarean delivery may inform nursing interventions for women with postpartum *** To explore the state of mind and coping style of women with depression after cesarean delivery guided by SOR *** Eighty postpartum depressed women with cesarean delivery admitted to the hospital between January 2022 and October 2023 were selected and divided into two groups of 40 cases each,according to the random number table *** the control group,the observation group adopted the problem-solving nursing model under SOR *** two groups were consecutively intervened for 12 weeks,and the state of mind,coping styles,and degree of post-partum depression were analyzed at the end of the *** The Edinburgh Postnatal Depression Scale and Hamilton Depression Scale-24-item scores of the observation group were lower than in the control group after care,and the level of improvement in the state of mind was higher than that of the control group(P<0.05).The level of coping with illness in the observation group after care(26.48±3.35)was higher than that in the control group(21.73±3.20),and the level of avoidance(12.04±2.68)and submission(8.14±1.15)was lower than that in the control group(15.75±2.69 and 9.95±1.20),with significant differences(P<0.05).CONCLUSION Adopting the problem-solving nursing model using SOR theory for postpartum depressed mothers after cesarean delivery reduced maternal depression,improved their state of mind,and coping level with illness.

关键词： Stimulus-organism-response theory Problem solving model Cesarean section Postpartum depression

A Novel Location Method for Interline Power Flow Controllers Based on Entropy Theory

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Protection and Control of Modern Power Systems 2024年第3期9卷 70-81页

作者： Qiuyu Li Baohong Li qin jiang Tianqi Liu Yin Yue Yingmin Zhang Sichuan University the School of Electrical Engineering Sichuan UniversityChengdu 610065China the College of Electrical Engineering and Information Technology Sichuan University

As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple ***,how to choose the appropriate location for the IPFC converters has not been discussed *** solve this problem,this paper proposes a novel location method for IPFC using entropy *** clarify IPFC’s impact on system power flow,its operation mechanism and control strategies of different types of serial converters are ***,to clarify the system power flow characteristic suitable for device location analysis,the entropy concept is *** this process,the power flow distribution entropy index is used as an optimization *** this index as a foundation,the power flow transfer entropy index is also generated and proposed for the IPFC location determination ***,electromechanical electromagnetic hybrid simulations based on ADPSS are implemented for *** are tested in a practical power grid with over 800 nodes.A modular multilevel converter(MMC)-based IPFC electromagnetic model is also established for precise *** results show that the proposed method can quickly and efficiently complete optimized IPFC location and support IPFC to determine an optimal adjustment in the N-1 fault cases.

关键词： Flexible alternative current transmission systems interline power flow controller modular multi-level converter optimized location method power flow transfer entropy

Photoinduced generation of alkyl and phthalimide nitrogen radicals from N-hydroxyphthalimide esters for the synthesis of benzophenone-type bioisosteres

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Science China Chemistry 2024年第10期67卷 3389-3396页

作者： Fei Li Jianyang Dong Huijuan Liao Jiayi Dang Xuechen Zhou Yuying Wang Chenya Wang qin jiang Gang Li Dong Xue Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education and School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119China

N-Hydroxyphthalimide(NHPI)esters have emerged as powerful sources of alkyl radicals generated by single-electron transfer,but homolysis of NHPI ester to produce an alkyl radical and a phthalimide nitrogen radical is still in its *** this study,we developed a light-induced method for generation of alkyl and phthalimide nitrogen radicals from NHPI esters and subsequent reactions of the radicals with[1.1.1]propellane and aryl aldehydes for rapid generation of bicycle[1.1.1]pentane *** method does not require metals or photosensitizers,features a broad substrate scope(90 examples)and excellent functional group tolerance,and can be used for the functionalization of structurally complex natural products and *** investigations indicate that the reaction involves photoinduced homolytic cleavage of the Cs_(2)CO_(3)-NHPI ester complex to produce alkyl and phthalimide nitrogen radicals and subsequent hydrogen atom transfer between the phthalimide nitrogen radical and the aldehyde to generate an acyl radical.

关键词： phthalimide nitrogen radicals aryl aldehydes hydrogen atom transfer bicycle[1.1.1]pentane ketones bioisosteres

Delivery room resuscitation intensity and associated neonatal outcomes of 24^(+0)-31^(+6) weeks'preterm infants in China:a retrospective cross-sectional study

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World Journal of Pediatrics 2024年第1期20卷 64-72页

作者： Si-Lu Wang Chun Chen Xin-Yue Gu Zhao-qing Yin Le Su Si-Yuan jiang Yun Cao Li-Zhong Du Jian-Hua Sun jiang-qin Liu Chuan-Zhong Yang Department of Neonatology Shanghai Key Laboratory of Maternal Fetal MedicineShanghai Institute of Maternal-Fetal Medicine and Gynecologic OncologyShanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityNo.2699Gaoke Western RoadPudong DistrictShanghai 201204China Department of Neonatology Affiliated Shenzhen Maternity and Child Healthcare HospitalSouthern Medical UniversityNo.2004Hongli RoadFutian DistrictShenzhen 518028China NHC Key Laboratory of Neonatal Diseases Fudan UniversityChildren's Hospital of Fudan UniversityShanghaiChina Department of Neonatology People's Hospital of DehongKunming Medical UniversityDehongChina Department of Neonatology Children's Hospital of Fudan UniversityShanghaiChina Department of Neonatology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of Neonatology Shanghai Children's Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Background The aim of this study was to review current delivery room(DR)resuscitation intensity in Chinese tertiary neonatal intensive care units and to investigate the association between DR resuscitation intensity and short-term outcomes in preterm infants born at 24+0_31+6 weeks gestation age(GA).Methods This was a retrospective cross-sectional *** source population was infants born at 24+0_31+6 weeks'GA who were enrolled in the Chinese Neonatal Network 2019 *** infants were categorized into five groups:(1)regular care;(2)oxygen supplementation and/or continuous positive airway pressure(O2/CPAP);(3)mask ventilation;(4)endotracheal intubation;and(5)cardiopulmonary resuscitation(CPR).The association between DR resuscitation and shortterm outcomes was evaluated by inverse propensity score-weighted logistic *** Of 7939 infants included in this cohort,2419(30.5%)received regular care,1994(25.1%)received O,/CPAP,1436(18.1%)received mask ventilation,1769(22.3%)received endotracheal intubation,and 321(4.0%)received CPR in the *** maternal age and maternal hypertension correlated with a higher need for resuscitation,and antenatal steroid use tended to be associated with a lower need for resuscitation(P<0.001).Severe brain impairment increased significantly with increasing amounts of resuscitation in DR after adjusting for perinatal *** strategies vary widely between centers,with over 50%of preterm infants in eight centers requiring higher intensity *** Increased intensity of DR interventions was associated with increased mortality and morbidities in very preterm infants in *** is wide variation in resuscitative approaches across delivery centers,and ongoing quality improvement to standardize resuscitation practices is needed.

关键词： Cardiopulmonary resuscitation Delivery room Endotracheal intubation Neonatal resuscitation Preterm

Carotid versus axillary artery cannulation for descending aorta remodeling in type A acute aortic dissection

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World Journal of Cardiology 2024年第10期16卷 564-573页

作者： qin jiang Tao Yu Ke-Li Huang Ke Liu Xi Li Sheng-Shou Hu Department of Cardiac Surgery Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina Cardiac Surgery Center Sichuan Academy of Medical Sciences&Sichuan Provincial People’s HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Arterial cannulation sites for the surgical repair of type A aortic dissection(AAD)have evolved from right axillary artery(AA)cannulation to bilateral carotid artery(CA)based of femoral artery(FA)*** descending aorta remodeling is closely linked to the false lumen area ratio(FLAR),defined as false lumen area/aortic area,as well as to the incidence of renal replacement therapy(RRT).AIM To investigate the effect of the updated arterial cannulation strategy on descending aortic *** A total of 443 AAD patients who received FA combined cannulation between March 2015 and March 2023 were included in the *** these,209 received right AA cannulation and 234 received bilateral CA *** primary outcome was the change in FLAR,as calculated from computed tomography angiography in three segments of the descending aorta:Thoracic(S1),upper abdominal(S2),and lower abdominal(S3).Secondary outcomes were the incidence of RRT and the serum inflammation response,as observed by the levels of high sensitivity C reaction protein(hs-CRP)and Interleukin-6(IL-6).RESULTS The postoperative/preoperative ratio of FLAR in S2 and S3 was higher in the AA group compared to the CA group(S2:0.80±0.08 vs 0.75±0.07,P<0.001;S3:0.57±0.12 vs 0.50±0.12,P<0.001,respectively).The AA group also had a significantly higher incidence of RRT(19.1%vs 8.5%,P=0.001;odds ratio:2.533,95%CI:1.427-4.493)and higher levels of inflammation cytokines 24 h after the procedure[hr-CRP:117±17 vs 104±15 mg/L;IL-6:129(103,166)vs 83(69,101)pg/mL;both P<0.001]compared to the CA *** The CA cannulation strategy was associated with better abdominal aorta remodeling after AAD repair compared to AA cannulation,as observed by a greater change in FLAR and lower incidence of RRT.

关键词： Acute type A aortic dissection Bilateral carotid arterial cannulation Descending aortic remodeling False lumen area ratio Prognosis

Human immunodeficiency virus-associated dementia complex with positive 14-3-3 protein in cerebrospinal fluid:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2065-2073页

作者： Yun-Sen He Xiao-Hong qin Min Feng qin-jiang Huang Meng-Jun Zhang Li-Li Guo Ming-Bin Bao Ye Tao Hong-Yuan Dai Bo Wu Department of Neurosurgery Sichuan Lansheng Brain Hospital&Shanghai Lansheng Brain Hospital Investment Co.Ltd.Chengdu 610036Sichuan ProvinceChina Department of Psychiatry Sichuan Provincial Center for Mental HealthChengdu 610072Sichuan ProvinceChina Department of Geriatrics Municipal People’s Hospital in LuzhouLuzhou 646000Sichuan ProvinceChina Department of Neurosurgery Wenjiang District People’s Hospital of ChengduChengdu 611100Sichuan ProvinceChina Department of Neurosurgery Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of China ChengduChengdu 610072Sichuan ProvinceChina Department of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND Human immunodeficiency virus(HIV)-associated dementia(HAD)is a subcortical form of dementia characterized by memory deficits and psychomotor ***,HAD often presents with symptoms similar to those of Creutzfeldt-Jakob disease(CJD),particularly in patients with acquired immune deficiency syndrome(AIDS).CASE SUMMARY We report the case of a 54-year-old male who exhibited cognitive dysfunction and secondary behavioral changes following HIV infection and suspected prion *** patient was diagnosed with HIV during hospitalization and his cerebrospinal fluid tested positive for 14-3-3 *** electroencephalogram showed a borderline-abnormal periodic triphasic wave ***-enhanced magnetic resonance imaging revealed moderate encephalatrophy and ***,symptomatic treatment and administration of amantadine were pursued for presumed CJD,but the patient’s condition continued to *** contrast,the patient’s condition improved following anti-HIV *** individual is also the only patient with this prognosis to have survived over 4 ***,the diagnosis was revised to *** In the diagnostic process of rapidly progressive dementia,it is crucial to rule out as many potential causes as possible and to consider an autopsy to diminish diagnostic *** 14-3-3 protein should not be regarded as the definitive marker for *** laboratory screening for infectious diseases is essential to enhance diagnostic precision,especially in AIDS patients with potential ***,a trial of diagnostic treatment may be considered when additional testing is not feasible.

关键词： HIV-associated dementia Cognitive dysfunction Creutzfeld-Jakob disease Rapidly progressive dementia Case report

清代农家账簿中的乡村价格体系——以浙南石仓地区为例

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求索 2024年第4期 95-106页

作者：蒋勤上海交通大学历史系上海200240

近年来,海量明清地方文献进入公藏机构,如何凭借零散的契约、账簿、票据等史料开辟新论题或是检验经典命题,成为亟待突破的难题。通过对民间账簿开展全面释读,并整体核算和变量提取,或可形成基于民间文书的价格研究新范式。以清代浙南... 详细信息

近年来,海量明清地方文献进入公藏机构,如何凭借零散的契约、账簿、票据等史料开辟新论题或是检验经典命题,成为亟待突破的难题。通过对民间账簿开展全面释读,并整体核算和变量提取,或可形成基于民间文书的价格研究新范式。以清代浙南松阳县石仓的农家账簿为核心史料,可构建一个19世纪地方食物类价格的体系及相对序列。在民间文书研究中,采用统一折米的方式可解决不同时空度量衡和货币不一致难题,提供了简易且有效的比较物价的方案。研究发现,米价较稳定,其次是猪肉价格,最后是盐价和糖价等外部商品的价格;而折米价格的变动则反映商品供应能力和需求的相对变动,从中或可窥见乡村市场与产业的兴衰。整体性分析和量化方法的结合,为系统发掘地方文献的研究价值开辟了新路。

关键词：石仓食物价格乡村市场

清代乡民的饮食结构、生活水平与阶层差异——基于1820—1949年浙南乡民食材类型与食单配置的分析

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南京大学学报（哲学．人文科学．社会科学） 2024年第3期61卷 127-141,160页

作者：蒋勤冯大诚上海交通大学历史系上海市200240

在有关大分流的争论中,基于民众真实消费史料的分析较为罕见。通过考察1820年至1949年间石仓农家账簿,能够了解近代浙南地区乡民的食材类型以及各类仪式和日常生活的食单配置。在食材类型方面,石仓乡民的主食是米和面,极少为玉米、番薯... 详细信息

在有关大分流的争论中,基于民众真实消费史料的分析较为罕见。通过考察1820年至1949年间石仓农家账簿,能够了解近代浙南地区乡民的食材类型以及各类仪式和日常生活的食单配置。在食材类型方面,石仓乡民的主食是米和面,极少为玉米、番薯等;荤食以猪肉为主,禽、蛋次之,罕见牛羊肉,但海产干货扮演重要角色;其他副食方面,体现了鲜明的山林经济特色,包括茶油和各类菌菇,但未体现明确的移民特性。在食单配置方面,通过对四个典型场景所用食材的分析,发现婚嫁和祭祀等仪式均看重猪肉、禽蛋以及海货和香菇类食材;铁炉工人炼铁时更重米和肉的摄入,武童生备考时重视肉、禽、蛋、鱼等动物蛋白质的多元摄入,较少涉及菌菇类食材。分析表明,乡民饮食体现了明确的阶层差异,但移民群体特性并不明显,同时食材和食单具有很强的历史延续性。

关键词：饮食结构乡民饮食乡村阶层石仓文书