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Quantifying in situ N2 fluxes from an intensively managed calcareous soil using the 15N gas-flux method

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Journal of Integrative Agriculture 2022年第9期21卷 2750-2766页

作者： liu Yan wang Rui PAN zhan-lei ZHENG Xun-hua WEI Huan-huan zhang hong-rui MEI Bao-ling QUAN zhi fang Yun-ting JU Xiao-tang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences(CAS)Beijing 100029P.R.China College of Earth and Planet Science University of Chinese Academy of SciencesBeijing 100049P.R.China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China School of Ecology and Environment Inner Mongolia UniversityHohhot 010021P.R.China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110164P.R.China College of Tropical Crops Hainan UniversityHaikou 570228P.R.China

Denitrification-induced nitrogen(N) losses from croplands may be greatly increased by intensive ***,the accurate quantification of these losses is still challenging due to insufficient available in situ measurements of soil dinitrogen(N) *** carried out two one-week experiments in a maize-wheat cropping system with calcareous soil using theN gas-flux(NGF) method to measure in situ Nfluxes following urea *** ofN-labeled urea(99 atom%,130-150 kg N ha) were followed by irrigation on the 1 st,3 rd,and 5 th days after fertilization(DAF 1,3,and 5,respectively).The detection limits of the soil Nfluxes were 163-1 565,81-485,and 54-281 μg N mhfor the two-,four-,and six-hour static chamber enclosures,*** Nfluxes measured in 120 cases varied between 159 and 2 943(811 on average) μg N *** were higher than the detection limits,with the exception of only two *** Nfluxes at DAF 3 were significantly higher(by nearly 80%(P<0.01)) than those at DAF 1 and 5 in the maize experiment,while there were no significant differences among the irrigation times in the wheat *** Nfluxes and the ratios of nitrous oxide(NO) to the NO plus Nfluxes following urea application to maize were approximately 65% and 11 times larger,respectively(P<0.01),than those following urea application to *** differences could be mainly attributed to the higher soil water contents,temperatures,and availability of soil N substrates in the maize experiment than in the wheat *** study suggests that theNGF method is sensitive enough to measure in situ Nfluxes from intensively fertilized croplands with calcareous soils.

关键词： N2 fluxes 15N gas-flux method N2O/(N2O+N2)ratios detection limit intensive cropping system

PTC/NTC Behavior of PVDF Composites Filled with GF and CF

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Chemical Research in Chinese Universities 2008年第5期24卷 648-652页

作者： wang Xin-lei zhang Guo LI Ji-xin LI Zhuo-shi liu zhan-fang liu Xiu-qi Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University. Changehun 130012 P. R. China

Conductive polyvinylidene fluoride（PVDF）matrix composites filled with graphited fiber（GF）or carbon fiber（CF）were prepared by the melt-mixing *** breakage and length distribution of the fibers in the polymer matrix were studied by scanning electron microscope（SEM）and optical microscope（OM）observations,respectively. The differences in the positive temperature coefficient（PTC）effects of the composites were mainly attributed to inter-fiber contact *** elimination of the negative temperature coefficient（NTC）effect for CF/PVDF composite was because of an increase in the viscosity of the polymer *** the same filler content,CF could be more effective,to eliminate the NTC effect when compared with *** of 2%CF（mass fraction）in the PVDF composite with 7%GF（mass fraction）could effectively eliminate the NTC phenomenon of the composite.

关键词： Polyvinylidene fluoride Graphited fiber Carbon fiber Positive temperature coefficient effect Negative temperature coefficient effect

Designing two-dimensional ferroelectric materials from phosphorus-analogue structures

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Nano Research 2023年第4期16卷 5834-5842页

作者： Ziyuan liu lei tao Yan-fang zhang Jinbo Pan Shixuan Du Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Topological Quantum Computation Beijing 100190China

Two-dimensional(2D)ferroelectric(FE)materials with relatively low switching barrier and large polarization are promising candidates for next-generation miniaturized nonvolatile memory ***,we screen out 39 new 2D ferroelectric materials,MX(M:Group III-V elements;X:Group V-VII elements),in three phosphorus-analogue phases including black phosphorene-likeα-phase,blue phosphorus-likeβ-phase,and GeSe-likeγ-phase using high-throughput *** materials(α-SbP,γ-AsP,etc.)exhibit FE switching barriers lower than 0.3 eV/f.u.,ferroelectric polarization larger than 2×10^(−10)C/m,and high thermodynamic stability with energy above hull smaller than 0.2 eV/*** find that the larger the electronegativity difference between M and X,the larger the ferroelectric ***,larger electronegativity differences result in lower in-plane piezoelectric stress tensor(e11)for MX consisting of Group IV and VI elements and larger e11 for those consisting of Group V *** calculations predict a giant tunneling electroresistance in ferroelectric tunnel junctionα-Sb(Sn)P/α-SbP/α-Sb(Te)P(1.26×104%)and large piezoelectric strain coefficient inα-SnTe(396 pm/V),providing great opportunities to the design of non-volatile resistive memories,and high-performance piezoelectric devices.

关键词： two-dimensional(2D)materials ferroelectricity piezoelectricity ferroelectric tunnel junction

Quantitative characterization of pore structure of the CarboniferousePermian tight sandstone gas reservoirs in eastern Linqing depression by using NMR technique

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Petroleum Research 2018年第2期3卷 110-123页

作者： tao fang Likuan zhang Naigui liu Liqiang zhang Weimin wang Lan Yu Chao Li Yuhong lei School of Geosciences China University of PetroleumShandong266580China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing100029China Key Laboratory of Petroleum Resources Research Chinese Academy of SciencesBeijing100029China Institute of Quantum Electronics School of Electronics Engineering and Computer SciencePeking UniversityBeijing100871China Research Institute of Exploration and Development Sinopec Shengli Oilfield CompanyShandong257000China

Micro-nano scale pores can accurately and fastly be measured by the nuclear magnetic resonance(NMR)technique,which provides a new method to quantitatively characterize pore structures in tight *** on the method of calibration of mercury pressure data for NMR T_(2) spectrum,for the measurement inaccuracy due to the mercury saturation less than 100%in tight sandstone,the mercury pressure curve and T_(2) spectrum is used to cumulate from the maximum pore on the right boundary to the small pores in the left,the range of pore-throat radius measured by the mercury injection in the leftward cumulative curve is selected as a comparable interval of NMR pore-throat radius,and the longitudinal interpolation method and the least square method are utilized to construct the distribution curve of pore-throat radius transformed by T_(2) *** modified method is used to obtain NMR T_(2) spectrum,conversion coefficient of pore-throat radius and pore-throat radius distribution of the Carboniferous-Permian tight sandstone gas reservoirs in the eastern Linqing depression,and characteristics of reservoir pore structures are quantitatively investigated;in addition,in combination with analysis of thin section and scanning electron microscopy,the reservoir effectiveness and cause of the pore structure variability in the tight sandstone are also well *** results show that the NMR pore-throat radius curve obtained by the modified method has a high consistency with the mercury injection curve,and the NMR test accuracy of tight sandstone is significantly *** the study area,the pore-throat radius of the Carboniferous-Permian tight sandstone mainly ranges from 0.002 to 2 mm,the pore is generally submicro-nano scale,but the pore-throat radius distribution of different types of sandstone varies *** lithic quartz sandstone is rich in siliceous matter and poor in plastic detritus and matrix,generally dominated by submicro-scale pore-throats including m

关键词： NMR T_(2)spectrum Mercury injection Conversion coefficient Pore-throat Rock fabric Microfacies Tight sandstone Linqing depression

Maraviroc promotes recovery from traumatic brain injury in mice by suppression of neuroinflammation and activation of neurotoxic reactive astrocytes

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Neural Regeneration Research 2023年第1期18卷 141-149页

作者： Xi-lei liu Dong-Dong Sun Mu-Tian Zheng Xiao-Tian Li Han-hong Niu Lan zhang Zi-Wei Zhou hong-tao Rong Yi wang Ji-Wei wang Gui-Li yang Xiao liu fang-Lian Chen Yuan Zhou Shu zhang Jian-Ning zhang Department of Neurosurgery Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institute Key Laboratory of Post-Neuroinjury Repair and Regeneration in Central Nervous SystemTianjinChina Graduate School Tianjin Medical UniversityTianjinChina Department of Neurosurgery Tianjin Huanhu HospitalTianjin Key Laboratory of Cerebral Vascular and Neurodegenerative DiseasesTianjin Neurosurgical InstituteTianjinChina Department of Radiotherapy Tianjin Medical University General HospitalTianjinChina Department of Geriatrics Tianjin Medical University General HospitalTianjinChina Institute of Tianjin Geriatrics Tianjin Medical University General HospitalTianjinChina

Neuroinflammation and the NACHT,LRR,and PYD domains-containing protein 3 inflammasome play crucial roles in secondary tissue damage following an initial insult in patients with traumatic brain injury(TBI).Maraviroc,a C-C chemokine receptor type 5 antagonist,has been viewed as a new therapeutic strategy for many neuroinflammatory *** studied the effect of maraviroc on TBI-induced neuroinflammation.A moderate-TBI mouse model was subjected to a controlled cortical impact *** or vehicle was injected intraperitoneally 1 hour after TBI and then once per day for 3 consecutive *** blot,immunohistochemistry,and TUNEL(terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling)analyses were performed to evaluate the molecular mechanisms of maraviroc at 3 days *** results suggest that maraviroc administration reduced NACHT,LRR,and PYD domains-containing protein 3 inflammasome activation,modulated microglial polarization from M1 to M2,decreased neutrophil and macrophage infiltration,and inhibited the release of inflammatory factors after ***,maraviroc treatment decreased the activation of neurotoxic reactive astrocytes,which,in turn,exacerbated neuronal cell ***,we confirmed the neuroprotective effect of maraviroc using the modified neurological severity score,rotarod test,Morris water maze test,and lesion volume *** summary,our findings indicate that maraviroc might be a desirable pharmacotherapeutic strategy for TBI,and C-C chemokine receptor type 5 might be a promising pharmacotherapeutic target to improve recovery after TBI.

关键词： C-C chemokine receptor type 5(CCR5)antagonist high mobility group protein B1(HMGB1) maraviroc M1 microglia nuclear factor-κB pathway NACHT,LRR,and PYD domains-containing protein 3(NLRP3)inflammasome neuroinflammation neurological function neurotoxic reactive astrocytes traumatic brain injury

Numerical Investigation on Inclined Hydraulic Transport of Large Particles for Deepsea Mining

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China Ocean Engineering 2023年第3期37卷 420-432页

作者： liu lei LI Xin TIAN Xin-liang zhang Xian-tao XU Li-xin zhang Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China

Hydraulic transport in pipelines is the most promising conveying method for large ore particles in deepsea *** dynamic performances of particles during transportation in vertical,inclined and horizontal pipelines are significant for the design of hydraulic transport *** the present study,we focus on the statistical characteristics and flow regimes of the mixture composed of ore particles and seawater in the *** simulations are conducted by using Computational Fluid Dynamics(CFD)and Discrete Element Method(DEM).The influences of inclination angle and particle diameter are evaluated through two sets of numerical *** regulation of the inclined transport is totally different from that of the vertical transport,whereas the dynamics of the mixtures in inclined and horizontal pipes are similar.A number of particles accumulate on the pipe wall even with a small inclination *** hydraulic gradient and local concentration would occur when the inclination angle of the pipe is in the range of30°-60°.With the decrease of particle diameter,the particle flow becomes uniform,reflected by the almost uniform particle distribution in the vertical pipe and the clear interface between the suspended load and the bed-load in the inclined ***,small particles will introduce larger local concentrations and hydraulic gradients in the inclined pipe,which is not conducive to particle transport.

关键词： deepsea mining hydraulic transport inclined pipe numerical simulation

Differences in brain pathological changes between rotenone and 6-hydroxydopamine Parkinson＇s disease models

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Neural Regeneration Research 2018年第7期13卷 1276-1280页

作者： Lan-Xiang liu Dan Du zhan-Qiu wang Yuan fang tao Zheng Yan-Chao Dong Qing-lei Shi Min Zhao fang Xiao Juan Du Department of Magnetic Resonance Imaging Qinhuangdao Municipal No. 1 Hospital Qinhuangdao Hebei Province China Department of Intervention Qinhuangdao Municipal No. 1 Hospital Qinhuangdao Hebei Province China Siemens Ltd. Beijing China Department of Pathology Qinhuangdao Municipal No. 1 Hospital Qinhuangdao Hebei Province China Hebei Medical University Shijiazhuang Hebei Province China

Rotenone and 6-hydroxydopamine are two drugs commonly used to generate Parkinson＇s disease animal *** not only achieve degenerative changes of dopaminergic neurons in the substantia nigra,but also satisfy the requirements for iron ***,few studies have compared the characteristics of these two models by magnetic resonance *** this study,rat models of Parkinson＇s disease were generated by injection of 3 μg rotenone or 10 μg 6-hydroxydopamine into the right substantia *** 1,2,4,and 6 weeks after injection,coronal whole-brain T2-weighted imaging,transverse whole-brain T2-weighted imaging,and coronal diffusion tensor weighted imaging were conducted to measure fractional anisotropy and T2＊ values at the injury *** fractional anisotropy value on the right side of the substantia nigra was remarkably lower at 6 weeks than at other time points in the rotenone *** the 6-hydroxydopamine group,the fractional anisotropy value was decreased,but T2＊ values were increased on the right side of the substantia nigra at 1 *** findings confirm that the 6-hydroxydopamine-induced model is suitable for studying dopaminergic neurons over short periods,while the rotenone-induced model may be appropriate for studying the pathological and physiological processes of Parkinson＇s disease over long periods.

关键词： nerve regeneration fractional anisotropy T2* rotenone 6-hydroxydopamine Parkinson's disease magnetic resonance imaging diffusion tensor imaging dopaminergic neurons neural regeneration

Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score

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Journal of Geriatric Cardiology 2020年第3期17卷 155-159页

作者： Wei-Dong LIN Yu-Mei XUE fang-Zhou liu Xian-hong fang Xian-zhang zhan hong-tao LIAO Gary Tse Shu-Lin WU Guangdong Cardiovascular Institute Guangdong General HospitalGuangzhouChina Department of Medicine and Therapeutics Faculty of MedicineChinese University of Hong KongHong KongChina Li Ka Shing Institute of Health Sciences Faculty of MedicineChinese University of Hong KongHong KongChina

Objective To determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation(AF)and low CHA2DS2-VASc scores,which remain *** We retrospectively analyzed the baseline clinical characteristics,routine laboratory parameters,and echocardiographic measurements of 705 patients(71.1%male;mean age:52.10±9.64 years)with low CHA2DS2-VASc score(0 or 1;1 point for female sex)out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography(TEE)at Guangdong Cardiovascular Institute between January 2013 and December *** Patients with left atrial thrombus(LAT)or spontaneous echo contrast(SEC)on TEE(24/705,4%)showed a higher incidence rate of vascular disease(54.2%vs.32.9%,P=0.045)and non-paroxysmal AF(79.2%vs.29.4%,P<0.001),larger left atrial diameter(43.08±4.59 vs.36.02±5.53 mm,P<0.001),and lower left ventricular ejection fraction(58.23±8.82%vs.64.15±7.14%,P<0.001)than those *** logistic regression analysis identified left atrial diameter[odds ratio(OR)=1.171,95%confidence interval(CI):1.084–1.265,P<0.001]and non-paroxysmal AF(OR=3.766,95%CI:1.282–11.061,P=0.016)as independent risk factors for LAT/*** ROC curve analysis,a left atrial dimeter cutoff of 37.5 mm yielded 95.0%sensitivity and 62.7%specificity(AUC:0.847,P<0.0001,95%CI:0.793–0.914).Conclusion In patients with non-valvular AF with low CHA2DS2-VASc score,the presence of LAT or SEC was associated with left atrial enlargement,which had moderate predictive value,and non-paroxysmal AF.

关键词： Atrial fibrillation Left atrial diameter Left atrial spontaneous echo contrast Left atrial thrombus

Synthesis,optical properties and self-organization of blue-emitting butterfly-shaped dithienobenzosiloles

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Chinese Chemical Letters 2022年第9期33卷 4306-4312页

作者： Gaozhang Gou Zhaoling zhang tao Fan lei fang Mingxian liu Liangchun Li Shanghai Key Lab of Chemical Assessment and Sustainability School of Chemical Science and EngineeringTongji UniversityShanghai 200092China

Ten novel butterfly-shaped dithienobenzosilole-based luminogens,which are peripherally installed with a variety of substituents including hydrogen,phenyl and substituted phenyl groups,have been readily prepared via an iodine-induced intramolecular electrophilic double-cyclisation reaction and subsequent deiodination or coupling *** optical and electrochemical properties of these compounds were systematically investigated to clarify the relationships between their structures and properties,supported by theoretical *** compounds exhibit deep-blue to sky-blue emissions and high photoluminescence quantum yields up to 0.84 in solution and solid states which are regulated by the functional blades and their steric hindrance on theα–andβ–positions of thiophene *** high thermal-and photo-stabilities have been revealed and mainly attributed to the dithienobenzosilole core.

关键词： Dithienobenzosilole Luminogen Double-cyclisation Blue-emitting Photo-stability