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A colorimetric chemosensor based on new water-soluble PODIPY dye for Hg^(2+) detection

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Chinese chemical Letters 2015年第10期26卷 1241-1245页

作者： Xin-Dong Jiang Hai-Feng Yu Jiu-Li Zhao Chang-Liang Sun Ying Xie Lin-Jiu Xiao College of Applied Chemistry Key Laboratory of Rare-Earth Chemistry and Applying Liaoning Province Shenyang University of Chemical Technology Center of physical and Chemistry test Shenyang University of Chemical Technology

The phosphorus-containing PODIPY 1 as a chemosensor can detect Hg^2＋ by a color change from pink to violet red without the use of any instrumentation. PODIPY 1 was selective to Hg^2＋ with a remarkable absorption change, and addition of other relevant metal ions caused almost no absorption change. The new PODIPY dye 1 was sensitive to various concentrations of Hg^2＋. The energy gap between the HOMO and LUMO of the metal complex 1–Hg^2＋ is smaller than that of chemosensor 1, which is in good agreement with the red shift in the absorption observed upon treatment of 1 with Hg^2＋. The 1-based test strips were easily fabricated and low-cost, useful in practical and efficient Hg^2＋test kits.

关键词： PODIPY Hg^2＋ Colorimetric DFT Chemosensor

Cumulative Risk Assessment of Exposure to Heavy Metals through Aquatic Products in China

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Biomedical and Environmental Sciences 2021年第8期34卷 606-615页

作者： WANG Hui MAO Wei Feng JIANG Ding Guo LIU Si Jie ZHANG Lei NHC Key Laboratory of Food Safety Risk Assessment Chinese Academy of Medical Science Research UnitChina National Center for Food Safety Risk AssessmentBeijing 100022China Department of Physical and Chemical Test Jilin Provincial Center for Disease Control and PreventionChangchun 130062JilinChina

Objective This study aimed to assess the risk of cumulative exposure to Pb,Cd,Hg,and iAs through aquatic products consumed by Chinese people.Methods Heavy metal concentration data were obtained from the national food contamination monitoring program during 2013–2017.Consumption data were derived from the China National Food Consumption Survey in 2014 and the relative potency factor(RPF)method was used to estimate cumulative exposure for neurotoxicity and nephrotoxicity.Results The results demonstrated that the cumulative exposure based on neurotoxicity was below the lower confidence limit on benchmark doses of lead(BMDL01)for nephrotoxicity and the cumulative exposures were all lower than the provisional tolerable monthly intake(PTMI)of Cd.However,the margin of exposure values(MOEs)of the cumulative exposures for neurotoxicity in the 2–6 year-old group was close to 1 and the cumulative exposure level for nephrotoxicity accounted for 90.21%of the PTMI.Conclusion The cumulative exposures of the 2–6 year-old group to the four heavy metals did not reach(but came close to)the corresponding safety threshold for both neurotoxicity and nephrotoxicity.Given that there are still other food sources of these four heavy metals,it is necessary to more closely study their cumulative health effects.

关键词： Arsenic Lead Cadmium Mercury Aquatic products Heavy metals

Synthesis of aza-BODIPY dyes bearing the naphthyl groups at 1,7-positions and application for singlet oxygen generation

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Chinese chemical Letters 2019年第5期30卷 1055-1058页

作者： Xindong Jiang Tingjiang Zhang Changliang Sun Yanqiu Meng Linjiu Xiao College of Applied Chemistry Key Laboratory of Rare-earth Chemistry and Applying of Liaoning ProvinceShenyang University of Chemical TechnologyShenyang 110142China department of Chemistry Graduate School of ScienceHiroshima UniversityHigashi-Hiroshima 739-8526Japan Center of physical and Chemistry test Shenyang University of Chemical TechnologyShenyang 110142China College of Pharmaceutical and Biological Engineering Shenyang University of Chemical TechnologyShenyang 110142China

Using 2-vinylnaphthalene,aza-BODIPYs with the naphthyl groups at 1,7-positions were prepared and their photophysical properties were characterized.Due to attachment of the naphthyl groups at1,7-positions,aza-BODIPYs show long-wavelength absorption and emission in the near-infrared region.The singlet oxygen generation of the dibromo substituted aza-BODIPY with the naphthyl groups at1,7-positions as a photosensitizer was more effective than that of the corresponding aza-BODIPY with the phenyl groups at 1,7-positions.No photobleaching of the naphthyl-containing aza-BODIPY was observed and such NIR aza-BODIPY could be used for the singlet oxygen generation.

关键词： Aza-BODIPY NIR Fluorescent dye Naphthyl group PS

Pretreating near infrared spectra with fractional order Savitzky–Golay differentiation(FOSGD)

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Chinese chemical Letters 2015年第3期26卷 293-296页

作者： Kai-Yi Zheng Xuan Zhang Pei-Jin Tong Yuan Yao Yi-Ping Du Shanghai Key Laboratory of Functional Materials Chemistry and Research Centre of Analysis and TestEast China University of Science and Technology department of chemical Engineering National Tsing Hua University

With the aid of Riemann–Liouville fractional calculus theory,fractional order Savitzky–Golay differentiation（FOSGD） is calculated and applied to pretreat near infrared（NIR） spectra in order to improve the performance of multivariate calibrations.Similar to integral order Savitzky–Golay differentiation（IOSGD）,FOSGD is obtained by fitting a spectral curve in a moving window with a polynomial function to estimate its coefficients and then carrying out the weighted average of the spectral curve in the window with the coefficients.Three NIR datasets including diesel,wheat and corn datasets were utilized to test this method.The results showed that FOSGD,which is easy to compute,is a general method to obtain Savitzky–Golay smoothing,fractional order and integral order differentiations.Fractional order differentiation computation to the NIR spectra often improves the performance of the PLS model with smaller RMSECV and RMSEP than integral order ones,especially for physical properties of interest,such as density,cetane number and hardness.

关键词： Golay FOSGD fractional fitting smoothing utilized compute polynomial Liouville calibration

How to Tailor Porous Boron Nitride Properties for Applications in Interfacial Processes

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Accounts of Materials Research 2023年第2期4卷 143-155页

作者： Ioanna Itskou Anouk L’Hermitte Sofia Marchesini Tian Tian Camille Petit Barrer Centre Department of Chemical EngineeringImperial College LondonLondon SW72AZUnited Kingdom Barrer Centre Department of Chemical Engineering and Department of MaterialsImperial College LondonLondon SW72AZUnited Kingdom National physical Laboratory Teddington TW110LWUnited Kingdom

The research of new porous materials for applications in interfacial processes is key to addressing global energy and sustainability challenges.For example,porous materials can be used to store fuels such as hydrogen or methane or to separate chemical mixtures reducing the energy currently required by thermal separation processes.Their catalytic properties can be exploited to convert adsorbed molecules into valuable or less hazardous chemicals,thereby reducing energy consumption or pollutants emissions.Porous boron nitride(BN)has appeared as a promising material for applications in molecular separations,gas storage,and catalysis owing to its high surface area and thermal stability,as well as its tunable physical properties and chemistry.However,the production of porous BN is still limited to the laboratory scale,and its formation mechanism,as well as ways to control porosity and chemistry,are yet to be fully understood.In addition,studies have pointed toward the instability of porous BN materials when exposed to humidity,which could significantly impact performance in industrial applications.Studies on porous BN performance and recyclability when employed in adsorption,gas storage,and catalysis remain limited,despite encouraging preliminary studies.Moreover,porous BN powder must be shaped into macrostructures(e.g.,pellets)to be used commercially.However,common methods to shape porous materials into macrostructures often cause a reduction in the surface area and/or mechanical strength.In recent years,research groups,including ours,have started addressing the challenges discussed above.Herein,we summarize our collective findings through a selection of key studies.First,we discuss the chemistry and structure of BN,clarifying confusion around terminology and discussing the hydrolytic instability of the material in relation to its structure and chemistry.We demonstrate a way to reduce the instability in water while still maintaining high specific surface area.We propose a mechanism for the formation of porous BN and d

关键词： separation Porous catalysis

Late cardioprotection of exercise preconditioning against exhaustive exercise-induced myocardial injury by up-regulatation of connexin 43 expression in rat hearts

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Asian Pacific Journal of Tropical Medicine 2015年第8期8卷 646-651页

作者： Kai Wang Bai-Chao Xu Hai-Yun Duan Hua Zhang Fu-Song Hu College of Sports Science Qufu Normal University department of physical Education Hainan Medical University QiongZhou University physical test Room

Objective: To investigate the expression of myocardium connexin 43(Cx43) in late exercise preconditioning(LEP) cardioprotection. Methods: Eight-week-old adult male Sprague Dawley rats were randomly assigned into four groups(n=8). Myocardial injury was judged in accordance with serum levels of c Tn and NT-pro BNP as well as hematoxylin basicfuchsin picric acid staining of myocardium. Cx43 m RNA was detected by in situ hybridization and qualified by real-time fluorescence quantitative PCR. Cx43 protein was localized by immunohistochemistry and its expression level was determined by western blotting. Results: The LEP obviously attenuated the myocardial ischemia/hypoxia injury caused by exhaustive exercise. There was no significant difference of Cx43 m RNA level between the four groups. Cx43 protein level was decreased significantly in group EE(P<0.05). However, LEP produced a significant increase in Cx43 protein level(P<0.05), and the decreased Cx43 protein level in exhaustive exercise was significantly up-regulated by LEP(P<0.05). Conclusions: LEP protects rat heart against exhaustive exercise-induced myocardial injury by up-regulating the expression of myocardial Cx43.

关键词： Exercise preconditioning Exhaustive exercise Myocardial injury Cardioprotection Connexin 43

An automated nucleic acid detection platform using digital microfluidics with an optimized Cas12a system

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Science China Chemistry 2022年第3期65卷 630-640页

作者： Zhen Sun Kang-Feng Lin Ze-Hang Zhao Yang Wang Xin-Xin Hong Jian-Guang Guo Qing-Yu Ruan Lian-Yu Lu Xiao Li Rui Zhang Chao-Yong Yang Bo-An Li State Key Laboratory of Cellular Stress Biology Innovation Center for Cell Signaling Network and Engineering Research Center of Molecular Diagnostics of the Ministry of EducationSchool of Life SciencesXiamen UniversityXiamen 361005China MOE Key Laboratory of Spectrochemical Analysis&Instrumentation Key Laboratory of Chemical Biology of Fujian ProvinceState Key Laboratory of Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy MaterialsDepartment of Chemical EngineeringDepartment of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China department of Thoracic Surgery The First Affiliated HospitalXiamen UniversityXiamen 361005China

Outbreaks of both influenza virus and the novel coronavirus SARS-CoV-2 are serious threats to human health and life. It is very important to establish a rapid, accurate test with large-scale detection potential to prevent the further spread of the epidemic. An optimized RPA-Cas12a-based platform combined with digital microfluidics(DMF), the RCD platform, was established to achieve the automated, rapid detection of influenza viruses and SARS-CoV-2. The probe in the RPA-Cas12a system was optimized to produce maximal fluorescence to increase the amplification signal. The reaction droplets in the platform were all at the microliter level and the detection could be accomplished within 30 min due to the effective mixing of droplets by digital microfluidic technology. The whole process from amplification to recognition is completed in the chip, which reduces the risk of aerosol contamination. One chip can contain multiple detection reaction areas, offering the potential for customized detection.The RCD platform demonstrated a high level of sensitivity, specificity(no false positives or negatives), speed(≤30 min),automation and multiplexing. We also used the RCD platform to detect nucleic acids from influenza patients and COVID-19 patients. The results were consistent with the findings of q PCR. The RCD platform is a one-step, rapid, highly sensitive and specific method with the advantages of digital microfluidic technology, which circumvents the shortcomings of manual operation. The development of the RCD platform provides potential for the isothermal automatic detection of nucleic acids during epidemics.

关键词： nucleic acid detection digital microfluidics Cas12a influenza virus SARS-CoV-2

Modified Nonlinear Model of Arcsin-Electrodynamics

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Communications in Theoretical Physics 2016年第7期65卷 59-65页

作者： S.I.Kruglov department of chemical and physical Sciences University of Toronto

A new modified model of nonlinear arcsin-electrodynamics with two parameters is proposed and analyzed.We obtain the corrections to the Coulomb law. The effect of vacuum birefringence takes place when the external constant magnetic field is present. We calculate indices of refraction for two perpendicular polarizations of electromagnetic waves and estimate bounds on the parameter γ from the BMV and PVLAS experiments. It is shown that the electric field of a point-like charge is finite at the origin. We calculate the finite static electric energy of point-like particles and demonstrate that the electron mass can have the pure electromagnetic nature. The symmetrical Belinfante energy-momentum tensor and dilatation current are found. We show that the dilatation symmetry and dual symmetry are broken in the model suggested. We have investigated the gauge covariant quantization of the nonlinear electrodynamics fields as well as the gauge fixing approach based on Dirac's brackets.

关键词：非线性模型电动力学能量动量张量协变量子化对称性库仑定律恒定磁场电磁性质

How Reliable Are Surface Tension Data?

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Accounts of Materials Research 2022年第9期3卷 894-899页

作者： Bernette M.Oosterlaken Gijsbertus de With Laboratory of physical Chemistry Department of Chemical Engineering and ChemistryEindhoven University of Technology5600 MB EindhovenThe Netherlands

Surface(Gibbs or Helmholtz)energy is of importance in many areas of science and technology but notoriously difficult to measure.At one time,it was thought that cleavage experiments could yield proper surface energy values because surface energy is related to the(reversible)energy needed to create a unit area of surface.As reported in his classic paper,Obreimoff1 was only in a few cases able,after“healing”a cleavage crack,to measure a similar cleavage energy along the same plane as needed in the initial experiment.

关键词： surface. experiment. measure.