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Estimating purple-soil moisture content using Vis-NIR spectroscopy

Journal of Mountain Science 2020年第9期17卷 2214-2223页

作者： gou yu WEI Jie LI Jin-lin HAN Chen TU Qing-yan LIU Chun-hong School of Geography and Tourism Science Chongqing Normal UniversityChongqing 401331China Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area Chongqing 401331China

Soil moisture is essential for plant growth in terrestrial *** study investigated the visible-near infrared(Vis-NIR)spectra of three subgroups of purple soils(calcareous,neutral,and acidic)from western Chongqing,China,containing different water *** relationship between soil moisture and spectral reflectivity(R)was analyzed using four spectral transformations,and estimation models were established for estimating the soil moisture content(SMC)of purple soil based on stepwise multiple linear regression(SMLR)and partial least squares regression(PLSR).We found that soil spectra were similar for different moisture contents,with reflectivity decreasing with increasing moisture content and following the order neutral>calcareous>acidic purple soil(at constant moisture content).Three of the four spectral transformations can highlight spectral sensitivity to SMC and significantly improve the correlation between the reflectance spectra and *** and PLSRmethods provide similar prediction *** PLSR-based model using a first-order reflectivity differential(R?)is more effective for estimating the SMC,and gave coefficient of determination(v2),root mean square errors of validation(RMSEV),and ratio of performance to inter-quartile distance(RPIQ)values of 0.946,1.347,and 6.328,respectively,for the calcareous purple soil,and 0.944,1.818,and 6.569,respectively,for the acidic purple *** neutral purple soil,the best prediction was obtained using the SMLR method with R?transformation,yieldingv2,RMSEV and RPIQ values of 0.973,0.888 and 8.791,*** general,PLSR is more suitable than SMLR for estimating the SMC of purple soil.

关键词： Purple soil Soil moisture Vis-NIR spectroscopy Stepwise multiple linear regression Partial least squares regression

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Nocardia cyriacigeorgica infection in a patient with repeated fever and CD4+T cell deficiency:A case report

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World Journal of Clinical Cases 2023年第5期11卷 1175-1181页

作者： Xin Hong You-Qi Ji Meng-yuan Chen Xiao-yu gou yu-Mei Ge Department of Green Pharmaceutical Collaborative Innovation Center School of PharmacyZhejiang University of TechnologyHangzhou 310014Zhejiang ProvinceChina School of Medical Technology and Information Engineering Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina The Second Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Clinical Laboratory Zhejiang Provincial People's Hospital(Affiliated People's HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Nocardia pneumonia shares similar imaging and clinical features with pulmonary tuberculosis and lung neoplasms,but the treatment and anti-infective medication are completely ***,we report a case of pulmonary nocardiosis caused by Nocardia cyriacigeorgica(***),which was misdiagnosed as community-acquired pneumonia(CAP)with repeated *** SUMMARY A 55-year-old female was diagnosed with community-acquired pneumonia in the local hospital because of repeated fever and chest pain for two *** the anti-infection treatment failed in the local hospital,the patient came to our hospital for further *** computed tomography showed multiple patchy,nodular and strip-shaped high-density shadows in both lungs.A routine haematological examination was performed and showed abnormalities in CD19+B cells and CD4+T *** acid-fast bifurcating filaments and branching gram-positive rods were observed in the bronchoalveolar lavage fluid of the patient under an oil microscope,which was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry as *** patient’s condition quickly improved after taking 0.96 g compound sulfamethoxazole tablets three times a *** The antibiotic treatment of Nocardia pneumonia is different from that of common *** should be given to the pathogenic examination results of patients with recurrent *** pneumonia is an opportunistic *** with CD4+T-cell deficiency should be aware of Nocardia infection.

关键词： Nocardia pneumonia Nocardia cyriacigeorgica Matrix-assisted laser desorption ionization-time of flight mass spectrometry Infection Lung CD4+T-cell Case report

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Damped large amplitude oscillations in a solar prominence and a bundle of coronal loops

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Research in Astronomy and Astrophysics 2016年第11期16卷 19-28页

作者： Quan-Hao Zhang yu-Ming Wang Rui Liu Cheng-Long Shen Min Zhang Ting-yu gou Jia-Jia Liu Kai Liu Zhen-Jun Zhou Shui Wang CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary Sciences University of Science and Technology of China Hefei 230026 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China Collaborative Innovation Center of Astronautical Science and Technology Hefei 230026 China Mengcheng National Geophysical Observatory School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We investigate the evolutions of two prominences （P1, P2） and two bundles of coronal loops （L1, L2）, observed with SDO/AIA near the east solar limb on 2012 September 22. It is found that there were large-amplitude oscillations in P1 and L1 but no detectable motions in P2 and L2. These transverse oscillations were triggered by a large-scale coronal wave, originating from a large flare in a remote active region behind the solar limb. By carefully comparing the locations and heights of these oscillating and non-oscillating structures, we conclude that the propagating height of the wave is between 50 Mm and 130 Mm. The wave energy deposited in the oscillating prominence and coronal loops is at least of the order of 10-8 erg. Furthermore, local magnetic field strength and Alfv6n speeds are derived from the oscillating periods and damping time scales, which are extracted from the time series of the oscillations. It is demon- strated that oscillations can be used in not only coronal seismology, but also to reveal the properties of the wave.

关键词： Sun: filaments prominences -- Sun: flares -- Sun: oscillations -- waves

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Laser absorption spectroscopy for high temperature H_2O time-history measurement at 2.55 μm during oxidation of hydrogen

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Chinese Physics B 2018年第7期27卷 376-381页

作者： yu-Dan gou De-Xiang Zhang Yi-Jun Wang Chang-Hua Zhang Ping Li Xiang-yuan Li Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China College of Chemical Engineering Sichuan UniversityChengdu 610065China

Concentration time-histories of H20 were measured behind reflected shock waves during hydrogen combustion. Experiments were conducted at temperatures of 1117-1282 K, the equivalence ratios of 0.5 and 0.25, and a pressure at 2 atm using a mixture of H2/O2 highly diluted with argon. H2O was monitored using tunable mid-infrared diode laser absorption at 2.55 μm （3920.09 cm-1）. These time-histories provide kinetic targets to test and refine reaction mechanisms for hydrogen. Comparisons were made with the predictions of four detailed kinetic mechanisms published in the last four years. Such comparisons of H2O concentration profiles indicate that the AramcoMech 2.0 mechanism yields the best agreement with the experimental data, while CRECK, San Diego, and HP-Mech mechanisms show significantly poor predictions. Reaction pathway analysis for hydrogen oxidation indicates that the reaction H ＋ OH ＋ M = H20 ＋ M is the key reaction for controlling the H2O formation by hydrogen oxidation. It is inferred that the discrepancy of the conversion percentage from H to H20 among these four mechanisms induces the difference of performance on H2O time-history predictions. This work demonstrates the potential of time-history measurement for validation of large reaction mechanisms.

关键词： tunable diode laser absorption spectroscopy H20 time-history profile combustion process reac- tion mechanism

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Evaluation preparation technology of Xiaochaihu granules using fingerprint-peak pattern matching

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Journal of Pharmaceutical Analysis 2011年第2期1卷 119-124页

作者： yu-Qiong Wu yu- Qiang gou Jing Han Ying-Yan Bi Shi-Lan Feng Fang-Di Hu Chun- Ming Wang School of Pharmacy Lanzhou University Lanzhou 730000 China the Second People's Hospital of Gansu Province Lanzhou 730000 China Center for Disease Control and Prevention Lanzhou Military Area Command of Chinese People's Liberation Army Lanzhou 730000 China College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China

An approach was proposed to evaluate preparation technology by means of fingerprint-peak matching technology of high performance liquid chromatography with diode array detector （HPLC-DAD）. Similarity and hierarchical clustering analysis （HCA） were applied to identify the 15 batches of Xiaochaihu granules from different manufacturers and our laboratory, and peak pattern matching between the composite formulae and Radix Bupleuri Chinensis, which was one of the main ingredients of Xiaochaihu granules, was utilized to evaluate the preparation technology of Xiaochaihu granules via the indexes of the relative deviation of retention time （RT） and UV spectrum feature similarity of their corresponding peaks. Eleven matching peaks were found between Xiaochaihu granules and Radix Bupleuri Chinensis. However, the saikosaponin A and saikosaponin D, which are the important active components in Radix Bupleuri Chinensis, were not found in Xiaochaihu granules from any manufacturers. The peak areas of 11 characteristic peaks of Xiaochaihu granules samples formed a matrix of 11 × 15. The result of HCA showed that Xiaochaihu granules samples were divided into four kinds of category. Xiaochaihu granules samples from the same manufacturer were basically clustered of the same category. The results suggested that the saikosaponin A and saikosaponin D are prone to structural transformation under the condition of decoction and in the presence of the organic acidic components. These active components, existing in raw herb, might transform to a series of non-active secondary saikosaponin due to unfavourable preparation technology. So the conventional decoction-based preparation technology of Xiaochaihu granules might greatly affect its quality and therapeutic effectiveness. This study demonstrates that fingerprint-peak matching technology can not only be used for quality control of this composite formulae, but also provide some guidance for preparation technology of Xiaochaihu granules.

关键词： Xiaochaihu granules Radix Bupleuri Chinensis fingerprint-peak matching hierarchical clustering analysis

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The pharmacokinetic study of rutin in rat plasma based on an electrochemically reduced graphene oxide modified sensor

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Journal of Pharmaceutical Analysis 2016年第2期6卷 80-86页

作者： PeiZhang yu-Qiang gou Xia Gao Rui-Bin Bai Wen-Xia Chen Bo-Lu Sun Fang-Di Hu Wang-Hong Zhao School of Pharmacy Lanzhou University Lanzhou 730000 China Lanzhou Military Command Center for Disease Prevention and Control Lanzhou 730020 China Department of Stomatology Nanfang Hospital Southern Medical University Guangzhou 510000 China

An electrochemical method based on a directly electrochemically reduced graphene oxide （ERGO） film coated on a glassy carbon electrode （GCE） was developed for the rapid and convenient determination of rutin in plasma. ERGO was modified on the surface of GCE by one-step electro-deposition method. Electrochemical behavior of rutin on ERGO/GCE indicated that rutin underwent a surface-controlled quasi-reversible process and the electrochemical parameters such as charge transfer coefficient （α）, electron transfer number （n） and electrode reaction standard rate constant （ks） were 0.53, 2 and 3.4 s -1, respectively. The electrochemical sensor for rutin in plasma provided a wide linear response range of 4.70 × 10 ^-7 1.25 × 10^-5 M with the detection limit （s/n=3） of 1.84 × 10^-8 M. The assay was success- fully used to the pharmacokinetic study of rutin. The pharmacokinetic parameters such as elimination rate half-life （t1/2）, area under curve （AUC）, and plasma clearance （CL） were calculated to be 3.345 ± 0.647 rain, 5750 ±656.0 μg min/mL, and 5.891± 0.458 mL/min/kg, respectively. The proposed method utilized a small sample volume of 10 μL and had no complicated sample pretreatment （without deproteinization）, which was simple, eco-friendly, and time- and cost-efficient for rutin pharmacokinetic studies.

关键词： Electrochemically reduced graphene oxide Pharmacokinetics Rat plasma Rutin

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国外旅游研究知识体系演变与共现

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经济管理 2016年第11期42卷 159-173页

作者：余构雄华南理工大学经济与贸易学院广东广州510006

既有文献有少量以关键词为研究对象来探讨国内旅游研究相关信息,然而鲜见对国外旅游研究知识体系的研究。本文以国外旅游学术刊物影响因子及引用率排名最前的《Annals of Tourism Research》和《Tourism Management》1986—2015年载文... 详细信息

既有文献有少量以关键词为研究对象来探讨国内旅游研究相关信息,然而鲜见对国外旅游研究知识体系的研究。本文以国外旅游学术刊物影响因子及引用率排名最前的《Annals of Tourism Research》和《Tourism Management》1986—2015年载文的书写关键词为研究对象,采用文献计量法及内容分析法,历时性与共时性交替贯穿于研究中,通过可视化软件"引文空间分析"进行数据统计分析,籍此演绎国外旅游研究知识体系。研究结果显示:(1)旅游研究知识体系演变呈现宽泛—收缩,其本质是旅游研究知识体系的演变脉络逐渐清晰,其演变呈现"稳中有变""稳优于变"及"热点不再—热点演进—热点连贯"的特点;(2)构建了由旅游研究主要内容、旅游研究地理区域和旅游研究方法组成的国外旅游研究知识体系共现框架。最后,较为细致地探讨国内外旅游业及旅游研究发展历程、旅游研究主要内容、旅游研究地理区域、旅游研究方法的异同,以期为深化国内旅游研究提供借鉴与启示。

关键词：旅游研究知识体系演变共现引文空间

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Estimating the Texture of Purple Soils Using Vis-NIR Spectroscopy and Optimized Conversion Models

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Agricultural Sciences 2023年第2期14卷 202-218页

作者： Baina Chen Jie Wei Qiang Tang yu gou Chunhong Liu Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area School of Geography and Tourism Chongqing Normal University Chongqing China Chongqing Field Observation and Research Station of Surface Ecological Process in the Three Gorges Reservoir Area School of Geography and Tourism Chongqing Normal University Chongqing China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical Sciences Southwest University Chongqing China

Soil texture is an indicator of soil physical structure which delivers many ecological functions of soils such as thermal regime, plant growth, and soil quality. However, traditional methods for soil texture measurement are time-consuming and labor-intensive. This study attempts to explore an indirect method for rapid estimating the texture of three subgroups of purple soils (i.e. calcareous, neutral, and acidic). 190 topsoil (0 - 10 cm) samples were collected from sloping croplands in Tongnan and Beibei Districts of Chongqing Municipality in China. Vis-NIR spectrum was measured and processed, and stepwise multiple linear regression (SMLR), partial least squares regression (PLSR), and back propagation neural network (BPNN) models were constructed to inform the soil texture. The clay fractions ranged from 4.40% to 27.12% while sand fractions ranged from 0.34% to 36.57%, hereby soil samples encompass three textural classes (i.e. silt, silt loam, and silty clay loam). For the original spectrum, the texture of calcareous and neutral purple soils was not significantly correlated with spectral reflectance and linear models (SMLR and PLSR) exhibited low prediction accuracy. The correlation coefficients and the goodness-of-fits between soil texture and the transformed spectra of all soil groups increased by continuum-removal (CR), first-order differential (R'), and second-order differential (R") transformations. Among them, the R" had the best performance in terms of improving the correlation coefficients and the goodness-of-fits. For the calcareous purple soil, the SMLR exceeds PLSR and BPNN with a higher coefficient of determination (R2) and the ratio of performance to inter-quartile distance (RPIQ) values and lower root mean square error of validation (RMSEV), but for the neutral and acidic purple soils, the PLSR model has a better prediction accuracy. In summary, the linear methods (SMLR and PLSR) are more reliable in estimating the texture of the three purpl

关键词： Soil Texture Vis-NIR Spectra Stepwise Multiple Linear Regression Partial Least Squares Regression Backpropagation Neural Network

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IN－SITU　FTIR　AND　UV－VISIBLE－NEAR－IR　SPECTROELECTROOHEMICAL　STUDIES　OF　MIXED－VALENCE　ISOPOLYANION　Mo＿6O＿（19）￣（3－）　IN　APROTIC　MEDIA

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Chinese Chemical Letters 1995年第12期6卷 1059-1060页

作者： Hao Ran SUN gou yu YANG Jia Ning XU Ji Qing XU (Department of Chemistry,Chemistry, Jilin University, Changchan, 130023)

In the paper, we have studied the mixed-valence isopolyanion by cyclic voltammogram, in-situ UV-Visible-Near-IR and FTIR spectroelectrochemical methods in aprotic medium,such as methylene chloride.A number of hetero-- and iso--polyanions of molybdenum are re(luci})leto a series of mixed-valeDce compounds containing Mow and Mo t'. f 1 1These species exhibit intervalence transfer bands. This description ofthe electronic structure corresponds to cia88 H syetems in Robinand Day'8 classification of mixed--valence compounds t21. The electrochemical methods can prepare the mixed--valence compounds in which laceetructure of the parent oxidized form is generally retained. [31 In--situepectroelectrochemical studies have many advantages for product identification and for mechanistic studies of transition metal complexes in solution. t.1 Among theme are small electrolysis volumee that yield shortelectrolysis times, rapid time response for the measurement or kineticparameters, and the rapid in--situ generation of reactive species withBtable properties that preclude isolation [*** cyclic voltammogram indicates that the (TBA).Mo.O.. undergoestwo reductione, which are labeled ac reactions 1--2 and corre6pond tothe electron transfers given in eq. 1-- ***.O.g-- + e * Mo.O.g--' E./2=--0.690V -----------------------------(1)Mo.O.S-- + e - Mo.O.:-- ac- other products E.,.=--1.650V------(2)

关键词： FTIR SITU VISIBLE APROTIC AND Mo UV

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单向水道船舶进出港最佳排序模式

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大连海事大学学报 2008年第4期34卷 150-153,157页

作者：徐国裕郭涂城吴兆麟大连海事大学航海学院辽宁大连116026 高雄港引航站中国台湾高雄804 长荣大学航运管理系中国台湾台南711

为避免船舶在港口水域因为等候进出造成拥挤而导致碰撞,提出单向水道船舶进出港最佳排序模式.根据船载AIS提供的与船舶通行安全相关的资料,以泊位远近、船舶大小、船舶类型、船舶吃水等主因素及其他子因素作为船舶权重.在高雄港水域的... 详细信息

为避免船舶在港口水域因为等候进出造成拥挤而导致碰撞,提出单向水道船舶进出港最佳排序模式.根据船载AIS提供的与船舶通行安全相关的资料,以泊位远近、船舶大小、船舶类型、船舶吃水等主因素及其他子因素作为船舶权重.在高雄港水域的实例验证表明,该排序模式较人工排序模式在通航安全与通航效率方面具有较大优势,可为未来建立整合性船舶交通组织服务架构提供重要参考.

关键词：船舶进出港单向水道最佳排序模式船舶权重

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