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Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

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Petroleum Science 2024年第3期21卷 2112-2119页

作者： Yu-Guo Li chen He Chun-mao chen Fan Liu Quan Shi State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China State Key Laboratory of Coal Mining and Clean Utilization Beijing 100013China PetroChina Ningxia Petrochemical Company Yinchuan 750021NingxiaChina

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD)and organic sulfur *** after the recovery of H_(2)S from the sour water by the stripping process,the effluent still contains a high concentration of dissolved organic sulfur(DOS),which can have a huge bad *** chemical composition of dissolved organic matter(DOM)in refinery wastewater has been extensively studied,the investigation of recalcitrant DOS from sour waters remains *** the present study,chemical composition of sour water DOMs(especially DOS)was investigated using fluorescence spectroscopy(excitation-emission matrix,EEM)and mass spectrometry,including gas chromatography-mass spectrometry(GC-MS)and high-resolution Orbitrap *** GC-MS and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process,while compounds with high hydrophilicity and humification degree were found to be more *** Orbitrap MS results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated ***,the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms,particularly in the form of highly unsaturated and aromatic *** Orbitrap MS/MS results of CHOS-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates,disulfide bonds,*** the composition and structure of sour water DOS is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur Stripping process Refinery sourwater Orbitrap MS

Mechanism of slag pellets sticking on the wall of reduction pot in magnesium production by Pidgeon process

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Journal of Magnesium and Alloys 2024年第6期12卷 2397-2412页

作者： Jilei Xu Jinhui Liu Dong Guo mao chen Peixu Yang Rongbin Li Shaojun Zhang School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Province Industrial Technology Research Institute of Resources and Materials Zhengzhou UniversityZhengzhou 450001China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

In the preparation of magnesium by Pidgeon process,the phenomenon slag pellets sticking on the wall of reduction pot always appear,and the glaze sticking on the inner wall of the reduction pot is difficult to *** mechanism of this phenomenon is studied in this work by X-ray fluorescence spectrometer(XRF)measurement,electron probe microanalyzer scanning(EPMA)analysis,differential scanning calorimetry(DSC)analysis,and thermodynamic *** main components of the glaze are MgO,Ca_(12)Al_(14)F_(2)O_(32),CaF_(2),CaO,and a small amount of Ca_(4)Si_(2)O_(7)F_(2).The solid-liquid transition temperature of Ca_(12)Al_(14)F_(2)O_(32)and CaF_(2)is close to the production temperature of Pidgeon process,which leads to the bonding between the slag pellets and the pot *** loss of CaF_(2)in glaze layer will reduce the total amount of liquid phase and increase the temperature at which Ca_(12)Al_(14)F_(2)O_(32)is completely transformed into liquid phase,which causes glaze layer sticking on the inner wall of the reduction pot.

关键词： Pidgeon process Glaze Ca_(12)Al_(14)F_(2)O_(32) CaF_(2) Solid-liquid transition

Effect of foot reflexology on an infant with sensorineural hearing loss:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1437-1441页

作者： Yu-Jun Lee mao-Qing chen Jie Dong Graduate School Xi'an International Studies UniversityNorth Sichuan Medical UniversityXi'an 710061Shaanxi ProvinceChina Department of Neural Disease North Sichuan Medical UniversityNanchong 635200Sichuan ProvinceChina Department of Nursing North Sichuan Medical UniversityNachong 635200Sichuan ProvinceChina Key Laboratory for Artificial Intelligence and Cognitive Neuroscience of Language Xi’an International Studies UniversityXi’an 710128Shaanxi ProvinceChina

BACKGROUND Our study contributes to the further understanding of the mechanism of foot *** reflexology has been reported to affect hearing recovery,but no physiological evidence has been *** lack of evidence hampers the acceptance of the technique in clinical *** SUMMARY A girl was taken to North Sichuan Medical University Affiliated Hospital for a hearing screen by her *** parents reported that her hearing level was the same as when she was *** girl was diagnosed with sensorineural hearing loss(SNHL)by a doctor in the otolaryngology *** we introduced the foot reflexology project,the parents agreed to participate in the *** 6 months of foot reflexology treatment,the hearing threshold of the girl recovered to a normal level,below 30 *** Foot reflexology should be encouraged in clinical practice and for families of infants with SNHL.

关键词： Infant with sensorineural hearing loss Foot reflexology Functional connectivity Language development Case report

Development of a Front End Array for Broadband Phased Array Receiver

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Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai Wang Liang Cao Jun Ma Xue-Feng Duan Hao Yan mao-Zheng chen Yun-Wei Ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

Digital Beamforming Demonstration of a Microstrip Antenna Phased Array Feeds(PAF)at 1.25 GHz

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Research in Astronomy and Astrophysics 2024年第10期24卷 76-80页

作者： Peng Wu mao-Zheng chen Jian Li Kai Wang Liang Cao Han Yu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

We introduce the structure of a radio astronomy phased array feeds(PAF)beamforming *** a laboratory environment,we have demonstrated beamforming on a received 1.25 GHz sinusoidal signal and used digital weighting techniques to plot the 2D pattern of the *** radio frequency part of the demonstrator includes a 4×4 linearly polarized microstrip antenna array,all of which is connected in series with a low-noise *** signals from the central 4×2 array elements are injected into a radio frequency system-on-chip digital board,which can receive eight inputs with a bandwidth of 512 *** the principle of undersampling,the beamforming is completed at a frequency of 1.25 GHz for the offline data,and a 2D image of the beam is plotted using beam scanning technology.

关键词： Astronomical Instrumentation Methods and Techniques Astronomical Databases methods:data analysis

Transcatheter aortic valve replacement:A journey of two decades and beyond

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Chinese Medical Journal 2024年第9期137卷 1012-1015页

作者： Tianyuan Xiong mao chen Department of Cardiology West China HospitalSichuan UniversityChengduSichuan 610041China Laboratory of Cardiac Structure and Function Institute of Cardiovascular DiseasesWest China HospitalSichuan UniversityChengduSichuan 610041China

The number of patients with calcic aortic stenosis(AS)is 9.4 million according to 2019 Global Disease Burden estimates,which will continue to increase as the population ages.[1]For the treatment of symptomatic severe AS,transcatheter aortic valve replacement(TAVR)has evolved to be a well-established option across all risk spectra,with a rapid growth of procedures *** rise of TAVR initiates the revolution of the management of valvular heart diseases,from patient surveillance,the staging of disease,the use of multimodality imaging,the concept of the Heart Team,new designs and iterations of devices to technical innovations and the discovery of unmet clinical *** a consequence of the global adoption of TAVR,geographical differences in the epidemiology of AS and patient characteristics have also been further identi*** examination of the changing patient population,current applications and breakthroughs,and remaining challenges are crucial for the future of this ***,we discuss the temporal utilization of TAVR,the accumulation of evidence and progress of devices,the selection of patients,and some ongoing topics concerning the improvement of TAVR.

关键词： epidemiology breakthrough beyond

Frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 374-379页

作者： Jie Cai Wen-Wen Fan Yun-Hui Zhong Cai-Lan Wen Xiao-Dan Wei Wan-chen Wei Wan-Yan Xiang Jin-mao chen Department of Ophthalmology First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Digital and Intelligent Technology Transformation and Application Research Institute of Visual Function Tianjin 300000China Guangxi Medical University Nanning 530021Guangxi Zhuang Autonomous RegionChina

AIM:To investigate the frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university ***:Totally 158 student volunteers underwent routine vision examination in the optometry clinic of Guangxi Medical *** data were used to identify the different types of accommodation and nonstrabismic binocular vision dysfunction and to determine their *** analysis and logistic regression were used to examine the factors associated with these ***:The results showed that 36.71%of the subjects had accommodation and non-strabismic binocular vision issues,with 8.86%being attributed to accommodation dysfunction and 27.85%to binocular *** insufficiency(CI)was the most common abnormality,accounting for 13.29%.Those with these abnormalities experienced higher levels of eyestrain(χ2=69.518,P<0.001).The linear correlations were observed between the difference of binocular spherical equivalent(SE)and the index of horizontal esotropia at a distance(r=0.231,P=0.004)and the asthenopia survey scale(ASS)score(r=0.346,P<0.001).Furthermore,the right eye's SE was inversely correlated with the convergence of positive and negative fusion images at close range(r=-0.321,P<0.001),the convergence of negative fusion images at close range(r=-0.294,P<0.001),the vergence facility(VF;r=-0.234,P=0.003),and the set of negative fusion images at far range(r=-0.237,P=0.003).Logistic regression analysis indicated that gender,age,and the difference in right and binocular SE did not influence the emergence of these ***:Binocular vision abnormalities are more prevalent than accommodation dysfunction,with CI being the most frequent *** binocular refractive disparity leads to more severe eyestrain symptoms.

关键词： optometry clinic non-strabismic binocular vision dysfunction college students convergence insufficiency

Design and Application of an S-band Fast Radio Bursts Search Pipeline for the Nanshan 26 m Radio Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 111-117页

作者： Yan-Ling Liu mao-Zheng chen Jian Li Jian-Ping Yuan Rai Yuen Zhi-Yong Liu Hao Yan Wen-Long Du Nan-Nan Zhai Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Fast radio bursts(FRBs)are among the most studied radio transients in astrophysics,but their origin and radiation mechanism are still *** is a challenge to search for FRB events in a huge amount of observational data with high speed and high *** the rapid advancement of the FRB research process,FRB searching has changed from archive data mining to either long-term monitoring of the repeating FRBs or all-sky surveys with specialized ***,establishing a highly efficient and high quality FRB search pipeline is the primary task in FRB *** learning techniques provide new ideas for FRB search *** have detected radio bursts from FRB 20201124A in the L-band observational data of the Nanshan 26 m radio telescope(NSRT-26m)using the constructed deep learning based search pipeline named dispersed dynamic spectra search(DDSS).Afterwards,we further retrained the deep learning model and applied the DDSS framework to S-band *** this paper,we present the FRB observation system and search pipeline using the S-band *** carried out search experiments,and successfully detected the radio bursts from the magnetar SGR J1935+2145and FRB *** experimental results show that the search pipeline can complete the search efficiently and output the search results with high accuracy.

关键词： radio continuum general-methods data analysis-methods observational

三氟氯乙烯与甲基异丙烯基醚的光诱导共聚反应

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化学学报 2024年第2期82卷 126-131页

作者：易敬霖陈茂复旦大学高分子科学系聚合物分子工程国家重点实验室上海200433

氟聚合物综合性能优异,在诸多领域发挥了重要作用.三氟氯乙烯(chlorotrifluoroethylene,CTFE)与乙烯基醚共聚物被用于高性能涂料,但其较低的玻璃化转变温度对应用场景带来了局限.在本工作中,发展了CTFE与甲基异丙烯基醚(methyl isoprope... 详细信息

氟聚合物综合性能优异,在诸多领域发挥了重要作用.三氟氯乙烯(chlorotrifluoroethylene,CTFE)与乙烯基醚共聚物被用于高性能涂料,但其较低的玻璃化转变温度对应用场景带来了局限.在本工作中,发展了CTFE与甲基异丙烯基醚(methyl isopropenyl ether,MIE)的光照自由基共聚反应,在室温常压条件下合成了全新化学结构的氟烯烃与烯基醚共聚物.聚合反应过程符合一级动力学与交替共聚特征,通过控制链转移剂用量与MIE转化率可合成不同分子量的共聚物,表明该聚合反应具备一定的可控性,但共聚物分子量分布较宽、链末端保真度有限.在此基础上,本工作首次揭示了CTFE-MIE共聚物比CTFE-乙烯基乙醚共聚物的玻璃化转变温度提高了近50℃,有助于进一步开发高性能氟聚合物材料.

关键词：氟聚合物共聚物光照聚合可逆失活自由基聚合三氟氯乙烯