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Thermal Behaviour of Some New Polyoxometalate Complexes of Ciprofloxacin with Keggin-type Heteropoly Acids

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Chemical Research in Chinese Universities 2005年第3期21卷 258-263页

作者： WANGDun-jia FANGZheng-dong HANDe-yan DepartmentofChemistryandEnvironmentalengineering HubeiNormalUniversityHuangshi435002P.R.China

Four polyoxometalate complexes, (CPFX·HCl)_3H_4SiW_~12 O_~40 , (CPFX·HCl)_3H_3PW_~12 O_~40 , (CPFX·HCl)_3H_3PMo_~12 O_~40 and (CPFX·HCl)_4H_4SiMo_~12 O_~40 , were prepared from ciprofloxacin hydrochloride(CPFX·HCl) reacting with H_nXM_~12 O_~40 ·nH_2O(X=P,Si; M=W,Mo) in an aqueous solution, and characterized by elemental analysis, IR spectrometry and TG-DTA. The IR spectrum confirms the presence of Keggin-type anions of heteropoly acids and the characteristic functional groups of ciprofloxacin. The TG/DTA curves show that their thermal decomposition is a multi-step process including simultaneous collapse of the Keggin-type structure. At first, these compounds had a mass loss of water molecules, then several other mass losses occured due to the decomposition of ciprofloxacin hydrochloride and its fragments with the degradation of Keggin anions. The end product of decomposition is the mixture of WO_3(or MoO_3) and SiO_2(or P_2O_5), identified by X-ray diffraction and IR spectroscopy. The possible thermal decomposition mechanisms of these complexes are proposed. This study exemplified that the thermal stability of the complexes containing tungsten is much better than that of the complexes containing molybdenum.

关键词： Thermal decomposition Polyoxometalate complexes Keggin-type heteropoly acids Ciprofloxacin hydrochloride TG/DTA

Heat transfer analysis of magnesium alloy plate during transport process

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Journal of Magnesium and Alloys 2019年第2期7卷 291-296页

作者： Qichi le Weitao jia Fangkun Ning Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Heavy Machinery Engineering Research Center Ministry of EducationTaiyuan University of Science and TechnologyTaiyuan 030024China

Temperature detection and tracking of AZ31B magnesium alloy plate during the air-cooling transport process were investigated and carried out under different thicknesses and initial *** results show that there exists a sudden temperature drop in the range of 1/4 of width distanced from the *** the plate is cooled by 25-56°C,the maximum inhomogeneous temperature distribution under all process conditions will appear in width *** the air-cooling transport process,the temperature control model for predicting the average temperature of the Mg plate after a predetermined time period can be established by modifying the Stefan-Boltzmann empirical *** model mainly depends on the plate specifications and air-cooling time.

关键词： AZ31B magnesium alloy Temperature detection Transport process Temperature control model

Application of wavelet to strength log from scratch test

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1161-1170页

作者： He Zhang jia-Liang le Emmanuel Detournay Department of Civil Environmental and Geo-EngineeringUniversity of MinnesotaMinneapolisMN55455USA

This paper proposes a methodology to construct logs of rock strength from the cutting force signal recorded in scratch tests conducted in the ductile *** approach,which is based on the application of discrete wavelet transforms,recognizes the existence of two length scales[c and[*** strength length scale[c represents the length over which it is meaningful to measure strength,while the repeatability length scale[r is related to the resolution at which the force signal must be observed to become insensitive to the stochastic micro-failure events triggered by the motion of the *** is postulated that the original cutting force signal,assumed to be sampled at a high enough frequency,can be decomposed into a deterministic signal intrinsic to the rock and a stochastic one resulting from discrete rock failure *** technique of multiresolution analysis based on the maximal overlap discrete wavelet transform is applied as a low-pass filter to the original cutting force signals so as to wipe out the high-frequency components associated with the stochastic rock failure events.A criterion to determine the optimum cutoff frequency of the low-pass filter and the corresponding repeatability length scale is discussed in terms of the correlation coefficients between different filtered *** is shown that the low-pass filtered signals obtained at the optimum cutoff frequency have two salient features:(i)repeatability over different tests conducted at the same depth of cut on the same sample,and(ii)variability along the cutting *** excellent repeatability reveals that the deterministic background trend of the original force signals is relevant to the rock strength property,and the variability of the background trend captures the spatial variation of the rock strength.

关键词： Scratch tests Intrinsic specific energy Rock heterogeneity Wavelet method

Removal of GaN film over AlGaN with inductively coupled BCl_(3)/Ar atomic layer etch

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Chinese Physics B 2022年第1期31卷 613-617页

作者： jia-le Tang Chao Liu School of Physics and Electronic Engineering Jiangsu Normal University(JSNU)Xuzhou 221116China

Atomic layer etching(Ale)of thin film GaN(0001)is reported in detail using sequential surface modification by BCl_(3) adsorption and removal of the modified surface layer by low energy Ar plasma exposure in a reactive ion etching *** estimated etching rate of GaN is~0.74 nm/*** GaN is removed from the surface of AlGaN after 135 *** study the mechanism of the etching,the detailed characterization and analyses are carried out,including scanning electron microscope(SEM),x-ray photoelectron spectroscopy(XPS),and atomic force microscope(AFM).It is found that in the presence of GaCl_(x) after surface modification by BCl_(3),the GaCl_(x) disappears after having exposed to low energy Ar plasma,which effectively exhibits the mechanism of atomic layer *** technique enables a uniform and reproducible fabrication process for enhancement-mode high electron mobility transistors with a p-GaN gate.

关键词： atomic layer etch GaN high electron mobility transistor

Effective exposure of nitrogen heteroatoms in 3D porous graphene framework for oxygen reduction reaction and lithium–sulfur batteries

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Journal of Energy Chemistry 2018年第1期27卷 167-175页

作者： jia-le Shi Cheng Tang jia-Qi Huang Wancheng Zhu Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Advanced Research Institute for Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Chemical Engineering Qufu Normal UniversityQufu 273165ShandongChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China CAS Key Laboratory of Carbon Materials.Institute of Coal Chemistry Chinese Academy of SciencesTaiyuan 030001ShanxiChina

The introduction of nitrogen heteroatoms into carbon materials is a facile and efficient strategy to regulate their reactivities and facilitate their potential applications in energy conversion and storage. However,most of nitrogen heteroatoms are doped into the bulk phase of carbon without site selectivity, which significantly reduces the contacts of feedstocks with the active dopants in a conductive scaffold. Herein we proposed the chemical vapor deposition of a nitrogen-doped graphene skin on the 3D porous graphene framework and donated the carbon/carbon composite as surface N-doped grapheme（SNG）. In contrast with routine N-doped graphene framework（NGF） with bulk distribution of N heteroatoms, the SNG renders a high surface N content of 1.81 at%, enhanced electrical conductivity of 31 S cm^（-1）, a large surface area of 1531 m^2 g^（-1）, a low defect density with a low I_D/I_G ratio of 1.55 calculated from Raman spectrum, and a high oxidation peak of 532.7 ℃ in oxygen atmosphere. The selective distribution of N heteroatoms on the surface of SNG affords the effective exposure of active sites at the interfaces of the electrode/electrolyte, so that more N heteroatoms are able to contact with oxygen feedstocks in oxygen reduction reaction or serve as polysulfide anchoring sites to retard the shuttle of polysulfides in a lithium–sulfur battery. This work opens a fresh viewpoint on the manipulation of active site distribution in a conductive scaffolds for multi-electron redox reaction based energy conversion and storage.

关键词： Nitrogen-doped graphene Chemical vapor deposition Oxygen reduction reaction Lithium-sulfur battery Porous carbon materials Exposure of active sites

Numerical analysis of a ventilated supercavity under periodic motion of the cavitator

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Journal of Hydrodynamics 2021年第6期33卷 1216-1229页

作者： Yun-hua jiang Zhi-hui Zou jia Li Yao Yao le-le Yang School of Ocean Engineering and Technology Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Department of Aerospace Engineering Harbin Engineering UniversityHarbin 150001China AVICJonhon Optronic Technology Co. Ltd.Luoyang 471003China

This paper presents a numerical simulation of the geometry and the pressure distribution of a ventilated supercavity at different cavitator amplitudes and periods of *** numerical method is validated by comparing with the results of a semi-empirical formula under specific *** is shown that the simulation can capture the boundary fluctuations of the ventilated supercavity and its internal pressure variations in a cavitator motion *** simulation results show that the supercavity boundary experiences wave-like deformations when the wavelength of the disturbance caused by the cavitator motion is comparable to the supercavity *** is also shown that the supercavity closure changes in form between a re-entrant jet and a twin vortex owing to the variations of the pressure difference between the outside and the inside of the supercavity near the closure *** maximum diameter of the ventilated supercavity exhibits periodic changes with a double peak in each cavitator motion cycle,caused by the corresponding changes of the difference between the internal and external *** the increase of the amplitude of motion of the cavitator,the supercavity boundary has enhanced wave-like undulations,with an increased maximum diameter,and with fluctuations in the cavitation *** the period of the cavitator motion increases,the wavelength of the disturbances caused by this motion becomes greater than the supercavity length,and so the wave-like undulations of the supercavity boundary and the maximum diameter of the supercavity gradually decrease,but the variations of the cavitation number ***,with the increase of the periods,the delay effects on the variations of the characteristics of the supercavity geometry caused by cavitator motion gradually decrease,and they practically vanish for large periods.

关键词： Ventilated supercavity geometrical and pressure characteristics cavitator motion

Advancing the quality of care and nursing practice through emancipatory reflection

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Frontiers of Nursing 2019年第1期6卷 1-4页

作者： Hong-Jing Yu dong-Lan Ling jia-le Hu Department of Nursing Administration The Second Affiliated Hospital of Guangzhou Medical University Department of Urologic Surgery The Second Affiliated Hospital of Guangzhou Medical University Department of Nurse Anesthesia Virginia Commonwealth University

Reflection is a fundamental skill of health-care professionals and plays an important role in ensuring the quality of care in health-care practice. It is believed that undertaking reflection in practice can help nurses develop an awareness of a sense of personal power and agency, cultivate their critical thinking ability and help them promote their professional development. However, reflection has not been introduced widely as a nursing curriculum in China, and literature shows that some clinical nurses lack critical thinking skills and critical reflective practice skills by reason of not receiving systematic education on reflection when they were at nursing ***, we present a series of seven articles focused on prevalent and interesting practice-based events to reflect on in this special issue. The main aim is to disseminate reflective methodology and techniques and present examples of reflective writing for *** is expected that these articles will help to lead Chinese nurses to adopt critical emancipatory reflective processes to bring about transformative actions.

关键词： Smyth’s framework critical emancipatory reflection quality of care nursing practice

Rapid and nondestructive layer number identification of two-dimensional layered transition metal dichalcogenides

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Rare Metals 2017年第9期36卷 698-703页

作者： jia-Peng Wu le Wang Li-Yuan Zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-Electronic Functional Materials&Micro-Nano Devices Renmin University of ChinaBeijing 100872China Department of Physics South University of Science and Technology of ChinaShenzhen 518055China

MoS2, MoSe2 and WSe2 thin flakes were fabricated by the standard micromechanical cleavage procedures. The thickness and the optical contrast of the atomic thin dichalcogenide flakes on SiO2/Si substrates were measured by atomic force microscopy（AFM） and spectroscopic ellipsometer. A rapid and nondestructive method by using reflection spectra was proposed to identify the layer number of 2D layered transition metal dichalcogenides on SiO2（275 nm）/Si substrates. The contrast spectra of 2D nanosheets with different layer numbers are in agreement with theoretical calculations based on Fresnel＇s law, indicating that this method provides an unambiguous and nondestructive contrast spectra fingerprint for identifying single-and few-layered transition metal dichalcogenides. The results will greatly help in fundamental research and application.

关键词： Transition metal dichalcogenides Opticalcontrast Layer number identification

Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3095-3112页

作者： Fengcheng Deng Dan Yang Lingxi Qing Yifei Chen Jilian Zou Meiling jia Qian Wang Runda jiang Lihua Huang College of Pharmacy Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina

The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain *** gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine ***,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host *** reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological *** coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological *** study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological *** pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional *** can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage *** findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases.

关键词： cyclic adenosine monophosphate emotional disorders gut microbiota neurodegenerative diseases neurological diseases protein kinase A reciprocal regulation signaling pathway strategy therapies