A new HPLC method has been developed for determining donepezil in human plasma. To find the optimum conditions, a derivatization reaction was performed in different media, and the reaction product was identified by NM...A new HPLC method has been developed for determining donepezil in human plasma. To find the optimum conditions, a derivatization reaction was performed in different media, and the reaction product was identified by NMR and GC-MS after a semi-preparative HPLC separation. Under optimized conditions, donepezil was derivatized by 9-fluorenylmethyl chloroformate in chloroform and carbonate buffer at pH 9.5 in the presence of NaI after solid-phase extraction from a plasma sample. The reaction product was quantified on a reversed-phase TRACER EXCEL ODS-A, 5 μm column using a mixture of acetonitrile–10 mM acetate buffer(pH 6.0)–THF(60:35:5, v/v/v) as the mobile phase with fluorescence detection at 264 nm(ex) and 313 nm(em). Fluoxetine was used as the internal standard. The total run-time of the analysis was about 10 min, and a clean chromatogram was obtained. The developed method was linear over the range of 1–100 ng/mL in 500 μL of plasma samples(r2>0.998). The intra-day and inter-day precision values were in the range of 2.6%–11.6%. The limit of quantification was 1 ng/mL.展开更多
A method for the analysis of the optical purity of a series of chiral substituted tetrahydroisoquinolines (THIQs) was developed. The method is based on pre-column derivatization of the analytes with the derivatization...A method for the analysis of the optical purity of a series of chiral substituted tetrahydroisoquinolines (THIQs) was developed. The method is based on pre-column derivatization of the analytes with the derivatization reagent (–)-(1R)-menthyl chloroformate. The derivatization reaction selectively gives diastereomeric carbamates that are resolvable on an achiral non-polar GC column. The developed technique covers variously substituted THIQs, which differ significantly in volatility, steric and electronic properties. In all cases, the resolution factors (R) exceeded the value of 1.5. The method represents a robust way of analysis of mixtures of THIQs, which are often present in various matrixes such as body fluids, tissues and reaction mixtures.展开更多
The polymerization of metyl methacrylate (MMA) was studied in detail by use of CuCl/L as a catalyst and cho-lesteryl chloroformate (CC) as an initiator. It was found that the atom transfer radical polymerization of MM...The polymerization of metyl methacrylate (MMA) was studied in detail by use of CuCl/L as a catalyst and cho-lesteryl chloroformate (CC) as an initiator. It was found that the atom transfer radical polymerization of MMA could proceed when L equals to a multidentate aliphatic amine ligand, N,N,N',N'',N″-penta(methyl acry-late)diethylenetriamine (MA5-DETA), and no polymerization was occurred while L=2,2'-bipyridine and 1,10- phenanthroline. The linear proportionality of the molecular weights to the conversions and straight lines observed in ln[M]0/[M] versus time plots indicated that the present polymerization system had the typical controlled polymeri-zation characteristics.展开更多
Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and part...Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and particularly,it is non-poisonable chemical.In this paper,we use DC to replace ultra-dry chloroform(UC)as the processing solvent for preparation of active layers of organic solar cells.First,we selected PM6:BTP-e C9 as the basic binary and counted 100 solar cells'data,from which comparable device performance were obtained with use of DC and UC.Interestingly,DC showed better reproducibility,superior storage under a nitrogen atmosphere and a little better performance than UC.Both DC and UC gave rise of comparable hole and electron mobilities and similar charge recombination losses.Second,we based PM6:Y6 and D18-Cl:Y6 as the binaries and similar effects were obtained from both UC and DC when counting 30 devices for each binary.Third,the universality of the use of DC for preparing highefficient OSCs were again checked with several binary and ternary systems.In all,this study demonstrate that DC can replace UC for use in the field of OSCs.展开更多
The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the ef...The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.展开更多
Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and eyes.However,resear...Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and eyes.However,research on chloroform vapor sensing is still in its early stages,primarily due to the lack of specific recognition motif.Here we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor(HMSS@CDs-PCs)for enhanced chloroform sensing.The colloidal PC packed with hollow mesoporous silica spheres provides an interconnected ordered macro-meso-hierarchical porous structure,ideal for rapid gas sensing utilizing the photonic bandgap shift as the readout signal.The as-synthesized CDs with pyridinic-N-oxide functional groups adsorbed in the hollow mesoporous silica spheres are found to not only serve as the chloroform adsorption sites,but also a molecular glue that prevents crack formation in the colloidal PC.The sensitivity of HMSS@CDs-PCs sensor is 0.79 nm ppm^(-1)and an impressively low limit of detection is 3.22 ppm,which are the best reported values in fast-response chloroform vapor sensor without multi-signal assistance.The positive response time is 7.5 s and the negative response time 9 s.Furthermore,relatively stable sensing can be maintained within a relative humidity of 20%-85%RH and temperature of 25-55℃.This study demonstrates that HMSS@CDs-PCs sensors have practical application potential in indoor and outdoor chloroform vapor detection.展开更多
[ Objective] The aim was to establish the method of extracting genomic DNA from sheep blood clot on the basis of the improvement of method for extracting genomic DNA from tissues. [Method]The genomic DNA with complete...[ Objective] The aim was to establish the method of extracting genomic DNA from sheep blood clot on the basis of the improvement of method for extracting genomic DNA from tissues. [Method]The genomic DNA with complete primary structure and high purity was obtained from the sheep blood clot after the steps of cutting the sheep blood clot with ophthalmic scissors, cell lysis with tissue DNA extracts and digested by proteinase K, extracting with phenol/chloroform and precipitating with ethanol were performed. [ Result] The concentration of the extracted DNA was 159.90 ±0.70 ng/μl and the ratio of the A260/A280 was 1.80 ＋0.01. The sheep microsatellite locus of BM203 was amplified by using the extracted DNA from the sheep blood clot as template of PCR, and the PCR result was perfect. [Conclusion]This method is simple and feasible, the quantity and quality of the extracted DNA can satisfy the demands for the subsequent researches. It is worth to extending and using for reference.展开更多
The preservatives used in food products are strictly monitored and regulated. The present study aims to imply a sensitive and reliable analytical method to quantify two classes of preservatives (i.e. carboxylic acid a...The preservatives used in food products are strictly monitored and regulated. The present study aims to imply a sensitive and reliable analytical method to quantify two classes of preservatives (i.e. carboxylic acid and phenolic compounds) in food by means of gas chromatography-mass spectrometry (GC-MS), aimed at monitoring the products available within the local stores. Target analytes were derivatized via aqueous-phase isobutyl chloroformate-mediated reaction followed by dispersive liquid-liquid microextraction (DLLME) method. The quantity and quality determination of the studied samples were assured by performing FASST approach in a single run GC-MS analysis. The combination of standard addition method with sample dilution compensated the effect of sample matrix on the quantitative determination of the tested preservatives in the examined samples. The concentrations of sorbic acid (SA) were 210 μg/mL and 1000 μg/mL in soft drink and sauces samples, respectively. On the other hand, sodium benzoate (226 μg/mL) was only found in soft drink, whereas, no parabens were detected in any samples collected from the local stores.展开更多
The dissociative electron attachment process for CHCl3 at different electric field have been studied with nitrogen as drift and carrier gas using corona discharge ionization source ion mobility spectrometry （CD-IMS）...The dissociative electron attachment process for CHCl3 at different electric field have been studied with nitrogen as drift and carrier gas using corona discharge ionization source ion mobility spectrometry （CD-IMS）. The corresponding electron attachment rate constants varied from 1.26×10-8 cm3/（molecules s） to 8.24×10-9 cm3/（molecules s） as the electric field changed from 200 V/cm to 500 V/cm. At a fixed electric field in the drift region, the attachment rate constants are also detected at different sample concentration. The ionmolecule reaction rate constants for the further reaction between Cl^- and CHCl3 are also detected, which indicates that the technique maybe becomes a new method to research the rate constants between ions and neural molecules. And the reaction rate constants between Cl- and CHCl3 are the first time detected using CD-IMS.展开更多
Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of ...Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of the 21 standard AAs were established using O-phthalaldehyde-9-fluorenylmethyl chloroformate(OPA-FMOC)pre-column derivation method.The AA components in PRA and PRR were characterized qualitatively and quantitatively,and different AAs were screened using pattern recognition technology.Results Twelve AAs were identified in both PRA and PRR.Meanwhile,aspartic acid,glutamic acid,arginine,alanine,and gamma-aminobutyric acid were screened as characteristic components,and their concentrations could effectively distinguish PRA from PRR.Conclusion The established characterization method,which is based on the characteristic spectra of AAs,is accurate,efficient,and sensitive and can effectively distinguish between PRA and PRR from different producing areas,thus providing a reference for the overall characterization and evaluation of Chinese medicinal materials.展开更多
An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described.The reaction of amines with benzyl chloroformate（Cbz-Cl） in the presence of PEG-600 at room temperature ...An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described.The reaction of amines with benzyl chloroformate（Cbz-Cl） in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent yields.The method is applicable to the N-Cbz protection of aliphatic（acyclic and cyclic） and aromatic amines.展开更多
To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laog...To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laogang MSW landfills, Shanghai, China. Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity. The maximum specific cell growth rates （μmax= 0.042 hr-1, R2= 0.995） was derived through Boltzmann simulation, and the apparent half-saturation constants （Km（app） = 7.08 mmol/L, R2 = 0.982） was calculated according to Michaelis-Menton hyperbolic model, indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs. By way of adding the strain JTA1 culture, the methane consumption of aged refuse reached 115 mL, almost two times of control experiment. In addition, high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers. At the chloroform concentration of 50 mg/L, the methane-oxidation rate of bio-cover reached 0.114 mL/（day.g）, much higher than the highest rate, 0.0135 mL/（day.g）, of reported bio-covers. In conclusion, strain JTA1 opens up a new possibility for environmental biotechnology, such as soil or landfills bioremediation and wastewater decontamination.展开更多
In this paper two newly developed hypercrosslinked resins were used to treat micropolluted drinking water and their static and kinetic adsorption were investigated at 293 K. The results show that these two adsorbents ...In this paper two newly developed hypercrosslinked resins were used to treat micropolluted drinking water and their static and kinetic adsorption were investigated at 293 K. The results show that these two adsorbents are superior to Amberlite XAD-4 for removing chloroform and trichloroethylene in aqueous solutions. The breakthrough capacity and the total capacities from mini-column adsorption studies for chloroform and trichloroethylene on XAD-4, ZH-01 and ZH-00 are calculated respectively under experimental conditions展开更多
The main purpose of this study was to investigate the active components of the Chinese medicine formula Shenqi San（SS） by high performance liquid chromatography with diode array detector and electrospray ionization-...The main purpose of this study was to investigate the active components of the Chinese medicine formula Shenqi San（SS） by high performance liquid chromatography with diode array detector and electrospray ionization-hybrid quadrupole time-of-flight mass spectrum（HPLC-DADESI-QTOF-MS）, and demonstrate the anticancer mechanism of SS on human lung adenocarcinoma A549 cells by evaluating the cell proliferation and apoptosis induction. The chloroform extraction of SS（CE-SS） was extracted from SS, while HPLC-DAD-ESI-QTOF-MS assay was performed to identify components of CE-SS. MTT assay was used to quantify the proliferation of A549 cells with the treatment of CE-SS. Apoptosis analysis was carried out by detecting phosphatidylserine（PS） externalization using the Annexin V-FITC Apoptosis Detection Kit and the stained cells were analyzed with a flow cytometer. DAPI staining assay was carried out to observe morphological characteristics of apoptotic cells. Western blotting was used to detect the expression of important signaling proteins including caspase-3,-8,-9, p53, Bax and Bcl-2. Eight compounds were identified through HPLC-DAD-ESI-QTOF-MS analysis and 3-pyridine carboxylic acid, barbatin C, scutebarbatine F and barbatine D might be the main compounds responsible for the antitumor effect of CE-SS. CE-SS suppressed the proliferation of lung cancer A549 cells in a time-and dose-dependent manner. By Annexin V-FITC/PI double staining, we found that treatment with CE-SS induced apoptosis in A549 cells. After 24-h exposure to CE-SS, the expression of cleaved-caspase-9, cleaved-caspase-8 and cleaved-caspase-3 protein was activated, the expression of p53 protein increased while the ratio of Bax/Bcl-2 also increased. This study identified the eight compounds of CE-SS, and demonstrated their anticancer effect on human lung adenocarcinoma A549 cells via induction of apoptosis.展开更多
Electrochemical dechlorination of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature. Palladium/foam-nickel （Pd/foam-Ni） and palladium/polymeric pyrrole ...Electrochemical dechlorination of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature. Palladium/foam-nickel （Pd/foam-Ni） and palladium/polymeric pyrrole film/foam-nickel （Pd/PPy/foam-Ni） composite electrodes which provided catalytic surface for reductive dechlorination of chloroform in aqueous solution were prepared using an electrodepositing method. Scanning electron microscope （SEM） micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode. The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 min, which is much higher than that of Pd/foam-Ni electrode.展开更多
Practicability of method for the Hydra regeneration assay on the prescreening teratogenic potential of chlorinated drinking water disinfection by products was studied through both the assays of toxicity of adult ...Practicability of method for the Hydra regeneration assay on the prescreening teratogenic potential of chlorinated drinking water disinfection by products was studied through both the assays of toxicity of adult Hydra (T) and inhibition of the growth of regeneration Hydra (I) by using chloroform, dichloromethane and chloroacetic acid. The results showed that T 50 / I 50 ratios of chloroform and chloroacetic acid were 2 77 and 6 16 respectively, with teratogenic potential. T 50 / I 50 ratio of dichloromethane was 1.69, with weaker teratogenic potential. These experimental results indicated preliminarily that the Hydra regeneration assay has certainly applied value as a prescreening assay for developmental toxicity.展开更多
Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA ex...Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA extraction is an essential step in gene expression study using RT-qPCR. In this study, we describe simple modifications to the TRIzol? RNA extraction protocol widely used in biology and these allow high-yield extraction of RNA from cells on resorbable calcium phosphates. Without the modifications, RNA is trapped in the co-precipitated calcium compounds, rendering TRIzol? extraction method infeasible. Among the modifications, the use of extra TRIzol? to dilute the lysate before the RNA precipitation step is critical for extraction of RNA from porous ?-tricalcium phosphate (?-TCP) discs. We also investigate the rationale behind the undesirable precipitation so as to provide clues about the modifications required for other resorbable materials with high application potential in bone tissue engineering.展开更多
Silver nanoparticles with different sizes have been prepared by microemulsion and have been surface-modified with C12H25SH.Electron spin resonance results indicate that there exist some kinds of surface local paramagn...Silver nanoparticles with different sizes have been prepared by microemulsion and have been surface-modified with C12H25SH.Electron spin resonance results indicate that there exist some kinds of surface local paramagnetic sites in capped Ag nanoparticles,which leads to the relation between electron spin resonance parameters and particle size deviating from Kawabata's description.Thereis a strong interaction between nanosilver and chloroform.The smaller the particles,the stronger the interaction.Transmission electron microscopy and ultravilolet-visible absorption spectra confirmed that Ag nanoparticles are well dispersed in chloroform,implying that a good dispersity of Ag nanoparticles in polymers could be obtained by means of solution mixing by using chloroform as the solvent.展开更多
The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation ...The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation during film formation,since solvent properties,including solvent effect on molecular crystallization,boiling point,and interaction parameters,can directly change the evolution pathways associated with thermodynamics and kinetics.Therefore,revealing the underlying solvent-regulated morphology mechanism is potential to provide guiding strategies for device optimization.In this study,chloroform,chlorobenzene,and toluene are used to process PM6:Y6 blends by slot-die printing to fabricate OPV devices.The chloroform printed film forms a fibrillar network morphology with enhanced crystallization,facilitating exciton dissociation,charge transport and extraction,resulting in an optimal power conversion efficiency of 16.22%.However,the addition of the additive chloronaphthalene in chloroform solution leads to over-crystallization of Y6,and thus,increasing domain size that exceeds the exciton diffusion length,resulting in lower device efficiency.In addition,both the chlorobenzene and toluene suppress the crystallization of Y6,which drastically decreased short-circuit current and fill factor.These results demonstrate the important role of processing solvent in dictating film morphology,which critically connects with the resultant printed OPV performance.展开更多
文摘A new HPLC method has been developed for determining donepezil in human plasma. To find the optimum conditions, a derivatization reaction was performed in different media, and the reaction product was identified by NMR and GC-MS after a semi-preparative HPLC separation. Under optimized conditions, donepezil was derivatized by 9-fluorenylmethyl chloroformate in chloroform and carbonate buffer at pH 9.5 in the presence of NaI after solid-phase extraction from a plasma sample. The reaction product was quantified on a reversed-phase TRACER EXCEL ODS-A, 5 μm column using a mixture of acetonitrile–10 mM acetate buffer(pH 6.0)–THF(60:35:5, v/v/v) as the mobile phase with fluorescence detection at 264 nm(ex) and 313 nm(em). Fluoxetine was used as the internal standard. The total run-time of the analysis was about 10 min, and a clean chromatogram was obtained. The developed method was linear over the range of 1–100 ng/mL in 500 μL of plasma samples(r2>0.998). The intra-day and inter-day precision values were in the range of 2.6%–11.6%. The limit of quantification was 1 ng/mL.
基金The authors would like to acknowledge the Grant Agency of the Czech Republic for funding this work through re-search grants GACR 104/09/1497 and P106/12/1276.
文摘A method for the analysis of the optical purity of a series of chiral substituted tetrahydroisoquinolines (THIQs) was developed. The method is based on pre-column derivatization of the analytes with the derivatization reagent (–)-(1R)-menthyl chloroformate. The derivatization reaction selectively gives diastereomeric carbamates that are resolvable on an achiral non-polar GC column. The developed technique covers variously substituted THIQs, which differ significantly in volatility, steric and electronic properties. In all cases, the resolution factors (R) exceeded the value of 1.5. The method represents a robust way of analysis of mixtures of THIQs, which are often present in various matrixes such as body fluids, tissues and reaction mixtures.
基金Project supported by the National Natural Science Foundation of China (No. 20474042).
文摘The polymerization of metyl methacrylate (MMA) was studied in detail by use of CuCl/L as a catalyst and cho-lesteryl chloroformate (CC) as an initiator. It was found that the atom transfer radical polymerization of MMA could proceed when L equals to a multidentate aliphatic amine ligand, N,N,N',N'',N″-penta(methyl acry-late)diethylenetriamine (MA5-DETA), and no polymerization was occurred while L=2,2'-bipyridine and 1,10- phenanthroline. The linear proportionality of the molecular weights to the conversions and straight lines observed in ln[M]0/[M] versus time plots indicated that the present polymerization system had the typical controlled polymeri-zation characteristics.
基金the financial supports from the Department of Science and Technology of Inner Mongolia Autonomous Region(No.2020GG0192)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2022ZD04)Inner Mongolia Normal University。
文摘Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and particularly,it is non-poisonable chemical.In this paper,we use DC to replace ultra-dry chloroform(UC)as the processing solvent for preparation of active layers of organic solar cells.First,we selected PM6:BTP-e C9 as the basic binary and counted 100 solar cells'data,from which comparable device performance were obtained with use of DC and UC.Interestingly,DC showed better reproducibility,superior storage under a nitrogen atmosphere and a little better performance than UC.Both DC and UC gave rise of comparable hole and electron mobilities and similar charge recombination losses.Second,we based PM6:Y6 and D18-Cl:Y6 as the binaries and similar effects were obtained from both UC and DC when counting 30 devices for each binary.Third,the universality of the use of DC for preparing highefficient OSCs were again checked with several binary and ternary systems.In all,this study demonstrate that DC can replace UC for use in the field of OSCs.
基金supported by the National Natural Science Foundation of China(Nos.52270165 and 51978537)the Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province。
文摘The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.
基金supported by the National Key Research and Development Program of China(No.2022YFB3205500)National Natural Science Foundation of China(Nos.U23A20360 and 62303192)QL wishes to thank Water Research Australia(WRA 1144/21)for funding support.
文摘Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and eyes.However,research on chloroform vapor sensing is still in its early stages,primarily due to the lack of specific recognition motif.Here we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor(HMSS@CDs-PCs)for enhanced chloroform sensing.The colloidal PC packed with hollow mesoporous silica spheres provides an interconnected ordered macro-meso-hierarchical porous structure,ideal for rapid gas sensing utilizing the photonic bandgap shift as the readout signal.The as-synthesized CDs with pyridinic-N-oxide functional groups adsorbed in the hollow mesoporous silica spheres are found to not only serve as the chloroform adsorption sites,but also a molecular glue that prevents crack formation in the colloidal PC.The sensitivity of HMSS@CDs-PCs sensor is 0.79 nm ppm^(-1)and an impressively low limit of detection is 3.22 ppm,which are the best reported values in fast-response chloroform vapor sensor without multi-signal assistance.The positive response time is 7.5 s and the negative response time 9 s.Furthermore,relatively stable sensing can be maintained within a relative humidity of 20%-85%RH and temperature of 25-55℃.This study demonstrates that HMSS@CDs-PCs sensors have practical application potential in indoor and outdoor chloroform vapor detection.
基金Supported by Natural Science Foundation of Shanxi Province(2007011081 )Returning Brains Project in Shanxi Province(2007066 )Agricultural Science and Technology Achievement Transformation Fund Project(2008GB2A300032)~~
文摘[ Objective] The aim was to establish the method of extracting genomic DNA from sheep blood clot on the basis of the improvement of method for extracting genomic DNA from tissues. [Method]The genomic DNA with complete primary structure and high purity was obtained from the sheep blood clot after the steps of cutting the sheep blood clot with ophthalmic scissors, cell lysis with tissue DNA extracts and digested by proteinase K, extracting with phenol/chloroform and precipitating with ethanol were performed. [ Result] The concentration of the extracted DNA was 159.90 ±0.70 ng/μl and the ratio of the A260/A280 was 1.80 ＋0.01. The sheep microsatellite locus of BM203 was amplified by using the extracted DNA from the sheep blood clot as template of PCR, and the PCR result was perfect. [Conclusion]This method is simple and feasible, the quantity and quality of the extracted DNA can satisfy the demands for the subsequent researches. It is worth to extending and using for reference.
文摘The preservatives used in food products are strictly monitored and regulated. The present study aims to imply a sensitive and reliable analytical method to quantify two classes of preservatives (i.e. carboxylic acid and phenolic compounds) in food by means of gas chromatography-mass spectrometry (GC-MS), aimed at monitoring the products available within the local stores. Target analytes were derivatized via aqueous-phase isobutyl chloroformate-mediated reaction followed by dispersive liquid-liquid microextraction (DLLME) method. The quantity and quality determination of the studied samples were assured by performing FASST approach in a single run GC-MS analysis. The combination of standard addition method with sample dilution compensated the effect of sample matrix on the quantitative determination of the tested preservatives in the examined samples. The concentrations of sorbic acid (SA) were 210 μg/mL and 1000 μg/mL in soft drink and sauces samples, respectively. On the other hand, sodium benzoate (226 μg/mL) was only found in soft drink, whereas, no parabens were detected in any samples collected from the local stores.
基金ACKNOWLEDGMENTS The work was support by the National Natural Science Foundation of China （No.20707025 and No.20907054） and the Excellent Youth Foundation of Anhui Province Scientific Committee （No.06045098）.
文摘The dissociative electron attachment process for CHCl3 at different electric field have been studied with nitrogen as drift and carrier gas using corona discharge ionization source ion mobility spectrometry （CD-IMS）. The corresponding electron attachment rate constants varied from 1.26×10-8 cm3/（molecules s） to 8.24×10-9 cm3/（molecules s） as the electric field changed from 200 V/cm to 500 V/cm. At a fixed electric field in the drift region, the attachment rate constants are also detected at different sample concentration. The ionmolecule reaction rate constants for the further reaction between Cl^- and CHCl3 are also detected, which indicates that the technique maybe becomes a new method to research the rate constants between ions and neural molecules. And the reaction rate constants between Cl- and CHCl3 are the first time detected using CD-IMS.
基金We thank for the funding support from the Guangdong Provincial Key Laboratory of Chinese Medicine for Prevention and Treatment of Refractory Chronic Diseases(No.2018B030322012).
文摘Objective To evaluate the difference between Baishao(Paeoniae Radix Alba,PRA)and Chishao(Paeoniae Radix Rubra,PRR)from different regions based on the characteristic spectra of amino acids(AAs).Methods Fingerprints of the 21 standard AAs were established using O-phthalaldehyde-9-fluorenylmethyl chloroformate(OPA-FMOC)pre-column derivation method.The AA components in PRA and PRR were characterized qualitatively and quantitatively,and different AAs were screened using pattern recognition technology.Results Twelve AAs were identified in both PRA and PRR.Meanwhile,aspartic acid,glutamic acid,arginine,alanine,and gamma-aminobutyric acid were screened as characteristic components,and their concentrations could effectively distinguish PRA from PRR.Conclusion The established characterization method,which is based on the characteristic spectra of AAs,is accurate,efficient,and sensitive and can effectively distinguish between PRA and PRR from different producing areas,thus providing a reference for the overall characterization and evaluation of Chinese medicinal materials.
基金the National Science and Technology Project of China(No.2009ZX09102-054)for financial support
文摘An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described.The reaction of amines with benzyl chloroformate（Cbz-Cl） in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent yields.The method is applicable to the N-Cbz protection of aliphatic（acyclic and cyclic） and aromatic amines.
基金supported by the National Natural Science Foundation of China (No. 51008322)the Natural Science Foundation Project of Chongqing (No. CSTC 2010BB7300,5309)the State Key Laboratory of Pollution Control and Resource Reuse (No. PCRRF10001)
文摘To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laogang MSW landfills, Shanghai, China. Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity. The maximum specific cell growth rates （μmax= 0.042 hr-1, R2= 0.995） was derived through Boltzmann simulation, and the apparent half-saturation constants （Km（app） = 7.08 mmol/L, R2 = 0.982） was calculated according to Michaelis-Menton hyperbolic model, indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs. By way of adding the strain JTA1 culture, the methane consumption of aged refuse reached 115 mL, almost two times of control experiment. In addition, high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers. At the chloroform concentration of 50 mg/L, the methane-oxidation rate of bio-cover reached 0.114 mL/（day.g）, much higher than the highest rate, 0.0135 mL/（day.g）, of reported bio-covers. In conclusion, strain JTA1 opens up a new possibility for environmental biotechnology, such as soil or landfills bioremediation and wastewater decontamination.
基金This work was supported by the Educational Bureau of Jiangsu Province, China (Grant Code 01KJD150004).
文摘In this paper two newly developed hypercrosslinked resins were used to treat micropolluted drinking water and their static and kinetic adsorption were investigated at 293 K. The results show that these two adsorbents are superior to Amberlite XAD-4 for removing chloroform and trichloroethylene in aqueous solutions. The breakthrough capacity and the total capacities from mini-column adsorption studies for chloroform and trichloroethylene on XAD-4, ZH-01 and ZH-00 are calculated respectively under experimental conditions
基金supported by grants from Doctoral Scientific Research Foundation of Hubei University of Chinese Medicine(No.5114-000912)Hubei University of Chinese Medicine Foundation For Young Scholar(No.5112-0007)
文摘The main purpose of this study was to investigate the active components of the Chinese medicine formula Shenqi San（SS） by high performance liquid chromatography with diode array detector and electrospray ionization-hybrid quadrupole time-of-flight mass spectrum（HPLC-DADESI-QTOF-MS）, and demonstrate the anticancer mechanism of SS on human lung adenocarcinoma A549 cells by evaluating the cell proliferation and apoptosis induction. The chloroform extraction of SS（CE-SS） was extracted from SS, while HPLC-DAD-ESI-QTOF-MS assay was performed to identify components of CE-SS. MTT assay was used to quantify the proliferation of A549 cells with the treatment of CE-SS. Apoptosis analysis was carried out by detecting phosphatidylserine（PS） externalization using the Annexin V-FITC Apoptosis Detection Kit and the stained cells were analyzed with a flow cytometer. DAPI staining assay was carried out to observe morphological characteristics of apoptotic cells. Western blotting was used to detect the expression of important signaling proteins including caspase-3,-8,-9, p53, Bax and Bcl-2. Eight compounds were identified through HPLC-DAD-ESI-QTOF-MS analysis and 3-pyridine carboxylic acid, barbatin C, scutebarbatine F and barbatine D might be the main compounds responsible for the antitumor effect of CE-SS. CE-SS suppressed the proliferation of lung cancer A549 cells in a time-and dose-dependent manner. By Annexin V-FITC/PI double staining, we found that treatment with CE-SS induced apoptosis in A549 cells. After 24-h exposure to CE-SS, the expression of cleaved-caspase-9, cleaved-caspase-8 and cleaved-caspase-3 protein was activated, the expression of p53 protein increased while the ratio of Bax/Bcl-2 also increased. This study identified the eight compounds of CE-SS, and demonstrated their anticancer effect on human lung adenocarcinoma A549 cells via induction of apoptosis.
文摘Electrochemical dechlorination of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature. Palladium/foam-nickel （Pd/foam-Ni） and palladium/polymeric pyrrole film/foam-nickel （Pd/PPy/foam-Ni） composite electrodes which provided catalytic surface for reductive dechlorination of chloroform in aqueous solution were prepared using an electrodepositing method. Scanning electron microscope （SEM） micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode. The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 min, which is much higher than that of Pd/foam-Ni electrode.
文摘Practicability of method for the Hydra regeneration assay on the prescreening teratogenic potential of chlorinated drinking water disinfection by products was studied through both the assays of toxicity of adult Hydra (T) and inhibition of the growth of regeneration Hydra (I) by using chloroform, dichloromethane and chloroacetic acid. The results showed that T 50 / I 50 ratios of chloroform and chloroacetic acid were 2 77 and 6 16 respectively, with teratogenic potential. T 50 / I 50 ratio of dichloromethane was 1.69, with weaker teratogenic potential. These experimental results indicated preliminarily that the Hydra regeneration assay has certainly applied value as a prescreening assay for developmental toxicity.
文摘Resorbable bioceramics are attractive for medical applications such as bone substitution. Biochemical analysis on cells cultured on these biomaterials is vital to predict the impact of the materials in vivo and RNA extraction is an essential step in gene expression study using RT-qPCR. In this study, we describe simple modifications to the TRIzol? RNA extraction protocol widely used in biology and these allow high-yield extraction of RNA from cells on resorbable calcium phosphates. Without the modifications, RNA is trapped in the co-precipitated calcium compounds, rendering TRIzol? extraction method infeasible. Among the modifications, the use of extra TRIzol? to dilute the lysate before the RNA precipitation step is critical for extraction of RNA from porous ?-tricalcium phosphate (?-TCP) discs. We also investigate the rationale behind the undesirable precipitation so as to provide clues about the modifications required for other resorbable materials with high application potential in bone tissue engineering.
基金Supported by the Foundation of the Ministry of Education of China for the Excellent Youth Scholars,and the Key Programs of the Ministry of Education of China under Grant Nos.98069,99198。
文摘Silver nanoparticles with different sizes have been prepared by microemulsion and have been surface-modified with C12H25SH.Electron spin resonance results indicate that there exist some kinds of surface local paramagnetic sites in capped Ag nanoparticles,which leads to the relation between electron spin resonance parameters and particle size deviating from Kawabata's description.Thereis a strong interaction between nanosilver and chloroform.The smaller the particles,the stronger the interaction.Transmission electron microscopy and ultravilolet-visible absorption spectra confirmed that Ag nanoparticles are well dispersed in chloroform,implying that a good dispersity of Ag nanoparticles in polymers could be obtained by means of solution mixing by using chloroform as the solvent.
基金financially supported by the National Natural Science Foundation of China(Nos.51973110,21734009,21905102 and 22109094)the Program of Shanghai Science and Technology Commission science and technology innovation action plan(Nos.20ZR1426200,20511103800,20511103802 and 20511103803)+2 种基金the Natural Science Foundation of Shandong Province(No.ZR2019LFG005)the Key research project of Shandong Province(No.2020CXGC010403)the Center of Hydrogen Science,Shanghai Jiao Tong University,China。
文摘The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics(OPVs).The choice of processing solvent has great impact on the crystallization and phase separation during film formation,since solvent properties,including solvent effect on molecular crystallization,boiling point,and interaction parameters,can directly change the evolution pathways associated with thermodynamics and kinetics.Therefore,revealing the underlying solvent-regulated morphology mechanism is potential to provide guiding strategies for device optimization.In this study,chloroform,chlorobenzene,and toluene are used to process PM6:Y6 blends by slot-die printing to fabricate OPV devices.The chloroform printed film forms a fibrillar network morphology with enhanced crystallization,facilitating exciton dissociation,charge transport and extraction,resulting in an optimal power conversion efficiency of 16.22%.However,the addition of the additive chloronaphthalene in chloroform solution leads to over-crystallization of Y6,and thus,increasing domain size that exceeds the exciton diffusion length,resulting in lower device efficiency.In addition,both the chlorobenzene and toluene suppress the crystallization of Y6,which drastically decreased short-circuit current and fill factor.These results demonstrate the important role of processing solvent in dictating film morphology,which critically connects with the resultant printed OPV performance.
