The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of th...The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of the C–C coupling reaction remains a significant obstacle in achieving both high activity and selectivity for C_(2+) production. In this study, we demonstrated the use of defect engineering to promote COER towards C_(2+) products by introducing single chlorine vacancy (SVCl) into two-dimensional (2D) non-noble transition metal dichlorides (TMCl_(2)). Density functional theory (DFT) calculations revealed that SVCl in TMCl_(2) exhibits low formation energies and high stability, ensuring its feasibility for synthesis and application in electrocatalysis. The introduction of three-coordinated, unsaturated metal sites substantially enhances the catalytic activity of TMCl_(2), facilitating effective CO activation. Notably, SVCl-engineered CoCl_(2) and NiCl_(2) nanosheets exhibit superior performance in COER, with SVCl@CoCl_(2) showing catalytic activity for ethanol and propanol production, and SVCl@NiCl_(2) favoring ethanol production due to a lower limiting potential and smaller kinetic barrier for C–C coupling. Consequently, defective 2D TMCl_(2) nanosheets represent a highly promising platform for converting CO into value-added C_(2+) products, warranting further experimental investigation into defect engineering for CO conversion.展开更多
The cyclizations of L-(+)-prolinol 1 derived from L-proline with (thio)phosphoro(-no)dichlorides 2 give 1,2,3-azaphosphaoxabicyclo[3.3.0] 3 consisting of unequal amounts of diastereoisomers, eight pairs of which have ...The cyclizations of L-(+)-prolinol 1 derived from L-proline with (thio)phosphoro(-no)dichlorides 2 give 1,2,3-azaphosphaoxabicyclo[3.3.0] 3 consisting of unequal amounts of diastereoisomers, eight pairs of which have been successfully separated by silica gel column chromatography or recrystallization.展开更多
The present paper covers three silabridged hafnocene dichlorides(1, 2 and 3) prepared by sequential reactions of α, ω-dichloropermethyl polysilane with cyclopentadienyl sodium, n-butyl lithium and hafnium tetrachlor...The present paper covers three silabridged hafnocene dichlorides(1, 2 and 3) prepared by sequential reactions of α, ω-dichloropermethyl polysilane with cyclopentadienyl sodium, n-butyl lithium and hafnium tetrachloride. Their structures were characterized by elemental analyses, UV, 1H(13C) NMR and MS. Furthermore the crystal and molecular structures of 1 and 2 were determined by X-ray diffraction method. The crystal of 1 is monoclinic, space group C2/c with a=1. 3401(4), b=0. 9977(3), c = 1. 0922(4) nm; β=94. 07(1)° V=3. 6342 nm3, Z = 2, Dc = 2.155 g·cm-3. The final deviation factor R = 0. 064. The crystal of 2 is monoclinic, space group P21/c with a=0.0847(1), b=1.5181(1), c=2.9824(2) nm; β= 94. 07(1)°? V=3.634 nm3; Dc= l. 805 g·cm-3. The final deviation factor R = 0. 033. The relationship between the silabridged structure and spectral properties is also discussed.展开更多
Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning ...Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning tunneling microscopy(STM)and atomic force microscopy(AFM).Moreover,we study the electrical properties of the charged solitons at zero electric field by measuring local contact potential difference(LCPD)via Kelvin probe force microscopy(KPFM)using the Δf(V)method.The compensation voltage corresponding to the vertex of the parabola is obtained by fitting the quadratic relationship between Δf and sample bias.The results show that,without an external electric field,the solitons behave as negatively charged entities.Meanwhile,the LCPD mapping characterizes the spatial distribution of the potential at the charged solitons,which agrees well with those obtained from STM band bending measurements.展开更多
Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell cultures.In this study,ratiometric O_(2)-sensing membranes were prepared by electr...Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell cultures.In this study,ratiometric O_(2)-sensing membranes were prepared by electrospinning,an easy,low-cost,scalable,and robust method for fabricating nanofibers.Poly(ε-caprolactone)and poly(dimethyl)siloxane polymers were blended with tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)dichloride,which was used as the O_(2)-sensing probe,and rhodamine B isothiocyanate,which was used as the reference dye.The functionalized scaffolds were morphologically characterized by scanning electron microscopy,and their physicochemical profiles were obtained by Fourier transform infrared spectroscopy,thermogravimetric analysis,and water contact angle measurement.The sensing capabilities were investigated by confocal laser scanning microscopy,performing photobleaching,reversibility,and calibration curve studies toward different dissolved O_(2)(DO)concentrations.Electrospun sensing nanofibers showed a high response to changes in DO concentrations in the physiological-pathological range from 0.5%to 20%and good stability under ratiometric imaging.In addition,the sensing systems were highly biocompatible for cell growth promoting adhesiveness and growth of three cancer cell lines,namely metastatic melanoma cell line SK-MEL2,breast cancer cell line MCF-7,and pancreatic ductal adenocarcinoma cell line Panc-1,thus recreating a suitable biological environment in vitro.These O_(2)-sensing biomaterials can potentially measure alterations in cell metabolism caused by changes in ambient O_(2)content during drug testing/validation and tissue regeneration processes.展开更多
AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis.METHODS: The mice were randomly divided into 2 groups(n = 50), con...AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis.METHODS: The mice were randomly divided into 2 groups(n = 50), control group and model group. The mice in model group were given ethanol(10%) in drinking water after injection of dibutyltin dichloride(DBTC)(8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein( 60 % ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin(FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen typeⅠ(COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1(MMP-1) and tissue inhibitor of metalloproteinases-1(TIMP-1) m RNA in the pancreas was assessed by real time PCR.RESULTS: DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group(P < 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 m RNA in pancreas decreased, but TIMP-1 m RNA increased at model group.CONCLUSION: DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis.展开更多
Crosslinking treatments for a commercially available aromatic polyamide reverse osmosis membrane were carried out to improve its chlorine resistance.The crosslinking agents including 1,6-hexanediol diglycidyl ether,ad...Crosslinking treatments for a commercially available aromatic polyamide reverse osmosis membrane were carried out to improve its chlorine resistance.The crosslinking agents including 1,6-hexanediol diglycidyl ether,adipoyl dichloride and hexamethylene diisocyanate ester with long flexible aliphatic chains and high reactivity with N-H groups were used in the experiments.Attenuated total reflective Fourier transform infrared spectra verified the successful preparation of highly crosslinked membranes by crosslinking treatments.It was suggested that the crosslinking agents were connected to membrane surface through the reactions with amine and amide Ⅱ groups,which is confirmed by surface charge measurements.Based on contact angle measurements,crosslinking treatments decreased membrane hydrophilicity by introducing methylene groups to membrane surface.With increasing amount of crosslinking agent molecules connected to membrane surface,the hydrolysis of unconnected functional groups of crosslinking agent produced polar groups and increased membrane hydrophilicity.The highly crosslinked membranes showed higher salt rejections and lower water fluxes as compared with the raw membrane.Since the active sites(N-H groups) vulnerable to free chlorine on membrane surface were eliminated by crosslinking treatments,the chlorine resistances of the highly crosslinked membranes were significantly improved by slighter changes in both water fluxes and salt rejections after chlorination.展开更多
An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byprod...An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. Treatment of primary or secondary alcohols with VH gave alkyl formates or alkyl chlorides by depending on the reaction conditions.展开更多
Disulfur dichloride is a hazardous substance, which is irritating to the eyes. It is significant to study the physical and dissociation properties under external electric fields. The bond length, energy, dipole moment...Disulfur dichloride is a hazardous substance, which is irritating to the eyes. It is significant to study the physical and dissociation properties under external electric fields. The bond length, energy, dipole moment, orbital energy level distribution, infrared spectra and dissociation properties of disulfur dichloride molecule under different external fields are obtained by using the density functional theory at the B3LYP/6-311++G(d, p) basis set level. In addition, ultraviolet-visible absorption spectra of the molecule in different electric fields are studied with configuration interaction-single excitation(CIS)/6-311++G(d, p) method. According to the results, it has been found that as the electric field exerted along the positive direction of the z-axis increases, the two sulfur-chlorine(S-Cl) bond lengths become longer and tend to break, while the sulfur-sulfur(S-S) bond length becomes shorter and the energy gap decreases. The infrared spectrum and ultraviolet-visible absorption spectra both exhibit red shift under electric field. Moreover, by scanning the potential energy surface of disulfur dichloride about S-Cl bond, the dissociation barrier decreases with the increase of positive electric field. When the external electric field arrives at 0.040 atomic units, the barrier disappears, meaning the dissociation of disulfur dichloride. The present results offer an important reference to further study of disulfur dichloride.展开更多
AIM:To analyze gene expression profiles in an experimental pancreatitis and provide functional reversal of hypersensitivity with candidate gene endothelin-1 antagonists.METHODS:Dibutyltin dichloride(DBTC) is a chemica...AIM:To analyze gene expression profiles in an experimental pancreatitis and provide functional reversal of hypersensitivity with candidate gene endothelin-1 antagonists.METHODS:Dibutyltin dichloride(DBTC) is a chemical used as a polyvinyl carbonate stabilizer/catalyzer,biocide in agriculture,antifouling agent in paint and fabric.DBTC induces an acute pancreatitis flare through generation of reactive oxygen species.Lewis-inbred rats received a single i.v.injection with either DBTC or vehicle.Spinal cord and dorsal root ganglia(DRG) were taken at the peak of inflammation and processed for transcriptional profiling with a cDNA microarray biased for rat brain-specific genes.In a second study,groups of animals with DBTC-induced pancreatitis were treated with endothelin(ET) receptor antagonists [ET-A(BQ123) and ET-B BQ788)].Spontaneous pain related mechanical and thermal hypersensitivity were measured.Immunohistochemical analysis was performed using anti-ET-A and ET-B antibodies on sections from pancreatic tissues and DRG of the T10-12 spinal segments.RESULTS:Animals developed acute pancreatic inflammation persisting 7-10 d as confirmed by pathological studies(edema in parenchyma,loss of pancreatic architecture and islets,infiltration of inflammatory cells,neutrophil and mononuclear cells,degeneration,vacuolization and necrosis of acinar cells) and the painrelated behaviors(cutaneous secondary mechanical and thermal hypersensitivity).Gene expression profile was different in the spinal cord from animals with pancreatitis compared to the vehicle control group.Over 260 up-regulated and 60 down-regulated unique genes could be classified into 8 functional gene families:circulatory/acute phase/immunomodulatory;extracellular matrix;structural;channel/receptor/transporter;signaling transduction;transcription/translation-related;antioxidants/chaperones/heat shock;pancreatic and other enzymes.ET-1 was among the 52 candidate genes upregulated greater than 2-fold in animals with pancreatic inflammation and visceral pain-related behavior.Treatments with the ET-A(BQ123) and ET-B(BQ-788) antagonists revealed significant protection against inflammatory pain related mechanical and thermal hypersensitivity behaviors in animals with pancreatitis(P < 0.05).Open field spontaneous behavioral activity(at baseline,day 6 and 30 min after drug treatments(BQ123,BQ788) showed overall stable activity levels indicating that the drugs produced no undesirable effects on normal exploratory behaviors,except for a trend toward reduction of the active time and increase in resting time at the highest dose(300 μmol/L).Immunocytochemical localization revealed that expression of ET-A and ET-B receptors increased in DRG from animals with pancreatitis.Endothelin receptor localization was combined in dual staining with neuronal marker NeuN,and glia marker,glial fibrillary acidic protein.ET-A was expressed in the cell bodies and occasional nuclei of DRG neurons in na ve animals.However,phenotypic expression of ET-A receptor was greatly increased in neurons of all sizes in animals with pancreatitis.Similarly,ET-B receptor was localized in neurons and in the satellite glia,as well as in the Schwann cell glial myelin sheaths surrounding the axons passing through the DRG.CONCLUSION:Endothelin-receptor antagonists protect against inflammatory pain responses without interfering with normal exploratory behaviors.Candidate genes can serve as future biomarkers for diagnosis and/or targeted gene therapy.展开更多
Bone metastases have a major impact on quality of life and survival of patients with advanced prostate cancer,in the last decade,the development and approval of substances inhibiting the vicious cycle of bone metastas...Bone metastases have a major impact on quality of life and survival of patients with advanced prostate cancer,in the last decade,the development and approval of substances inhibiting the vicious cycle of bone metastases have enabled the reduction of complications caused by bone metastases in patients with castration-resistant prostate cancer.These drugs have raised awareness of the importance of skeletal-related events which in the meantime represent an important end point also in trials using agents not specifically designed for bone lesions.Second-generation antihormona]drugs such as enzalutamide or abiraterone have been shown to have a positive impact on the incidence of skeletal complications and therefore provide an important tool in the armamentarium used for treating bone metastases.Radiopharmaceuticals such as radium-223 dichloride([^223Ra])have been demonstrated not only to reduce skeletal-related events and bone-related pain,but also to prolong overall survival,thereby being the first bone-targeting agent showing a survival benefit.As previous studies have not provided an obvious benefit of bone-targeted lesions in castration-sensitive disease,the use of these agents is not recommended.In oligometastatic prostate cancer,the role of local treatment of metastases using stereotactic radiation or radiosurgery is a matter of intense debates and may play an increasing role in the future.展开更多
1,4-Bis(triphenylphosphonium)-2-butene dichloride(BTPBDC) and 1,4-bis(triphenyl phosphonium)-2-butene dithiocyanate (BTPBDT) were prepared and used as phase-transfer catalysts.Alkyl halides were converted effi...1,4-Bis(triphenylphosphonium)-2-butene dichloride(BTPBDC) and 1,4-bis(triphenyl phosphonium)-2-butene dithiocyanate (BTPBDT) were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.展开更多
Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a no...Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a novel pre‐oxidation‐pyrolysis process,affording unprecedented dehydrochlorination activity with good durability.The best‐performing system was further modified with different precious metals(Au,Pt,and Ru)to promote the hydrochlorination chemistry between the in‐situ formed hydrogen chloride and acetylene co‐feed.The presence of metal centers intensifies the hydrochlorination activity but weakens the dehydrochlorination ability due to competitive adsorption between the two reactants at the metal sites.Superior coupling performance was achieved over C_(3)N_(4)/AC and single‐atom Au/C_(3)N_(4)/AC catalysts in cascade reactors.Our results strongly suggest that dehydrochlorination is an essential step in the coupling reaction,and the activation of acetylene and ethylene dichloride molecules requires different active sites that should be engineered in future work.展开更多
Ab initio study of the equilibrium structure, spectroscopy constants, and anharmonic force field for several isotopomers of germanium dichloride (70GeCl2, 72GECl2, and 76GeCl2) have been carried out at the MP2 and C...Ab initio study of the equilibrium structure, spectroscopy constants, and anharmonic force field for several isotopomers of germanium dichloride (70GeCl2, 72GECl2, and 76GeCl2) have been carried out at the MP2 and CCSD(T) levels of theory using cc-pVTZ basis set. The cal- culated geometries, rotational constants, vibration-rotation interaction constants, harmonic frequencies, anharmonic constants, quartic and sextic centrifugal distortion constants, cubic and quartic force constants are compared with experimental data. For small mass differences of the Ge isotopes, the isotopic effects for germanium dichloride are much weaker. The agreements are satisfactory for these two methods, but the deviations of CCSD(T) results are slightly larger than that of MP2, because of CCSD(T)'s inadequate treatment of electron correlation in hypervalent Cl atom.展开更多
8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The suppor...8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.展开更多
The intermolecular coupling of a nitro group with a cyano group mediated by a Sm(Hg) amalgam prepared from metal samarium powder and catalytic mercury dichloride was studied.
Some organogermanium oligomers with different side groups were synthesized via ligand substitution polymerization from I, l-dioxane complex of germanium dichloride with different organolithium compounds. The oligomers...Some organogermanium oligomers with different side groups were synthesized via ligand substitution polymerization from I, l-dioxane complex of germanium dichloride with different organolithium compounds. The oligomers were isolated through either precipitation from methanol or extraction using toluene with a yield of no less than 50%. The weight average molecular weight (M-w) of the oligomers is ranging from 1.4 x 10(3) to 5.9 x 10(3) depending on the type and alkyl length of the organolithium compounds used.展开更多
Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane (MAO) catalyst system under mild condition. High yield was...Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane (MAO) catalyst system under mild condition. High yield was gained and no other oligmer was detected. It was found that the ratio of AI/Zr is responsible for the selectivity of product.展开更多
A novel organotin hydration dibenzyltin dichloride has been synthesized and its crystal structure was determined by X-ray diffraction. The crystal belongs to monoclinic, space group Pc with a = 1.1918(5), b = 0.6199...A novel organotin hydration dibenzyltin dichloride has been synthesized and its crystal structure was determined by X-ray diffraction. The crystal belongs to monoclinic, space group Pc with a = 1.1918(5), b = 0.6199(2), c = 1.1074(5)nm, β = 106.899(7)°, V= 0.7828(8)nm3, Z = 2, Dc = 1.654 g/cm3,μ(MoKa) = 19.59 cm^-1, F(000) = 384, R = 0.0564 and RwR = 0.1427. The Sn-C bonds are 0.2140(9) and 0.2152(5) nm, Sn-Cl are 0.2385(4) and 0.2497(3) nm, and Sn-O is 0.2388(7) nm. The tin atom is five-coordinated in a distorted trigonal bipyramidal configuration. The study on the title complex has been performed with quantum chemistry calculation by means of G98W package on the Lanl2dz basis set. The stability of the complex as well as the orbital energies and composition characteristics of some frontier molecular orbitals has been investigated.展开更多
基金financially supported by the International Partnership Program of the Chinese Academy of Sciences(No.172GJHZ2022010MI)the Natural Science Funds for Distinguished Young Scholars of Heilongjiang Province(No.JC2018004).
文摘The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of the C–C coupling reaction remains a significant obstacle in achieving both high activity and selectivity for C_(2+) production. In this study, we demonstrated the use of defect engineering to promote COER towards C_(2+) products by introducing single chlorine vacancy (SVCl) into two-dimensional (2D) non-noble transition metal dichlorides (TMCl_(2)). Density functional theory (DFT) calculations revealed that SVCl in TMCl_(2) exhibits low formation energies and high stability, ensuring its feasibility for synthesis and application in electrocatalysis. The introduction of three-coordinated, unsaturated metal sites substantially enhances the catalytic activity of TMCl_(2), facilitating effective CO activation. Notably, SVCl-engineered CoCl_(2) and NiCl_(2) nanosheets exhibit superior performance in COER, with SVCl@CoCl_(2) showing catalytic activity for ethanol and propanol production, and SVCl@NiCl_(2) favoring ethanol production due to a lower limiting potential and smaller kinetic barrier for C–C coupling. Consequently, defective 2D TMCl_(2) nanosheets represent a highly promising platform for converting CO into value-added C_(2+) products, warranting further experimental investigation into defect engineering for CO conversion.
文摘The cyclizations of L-(+)-prolinol 1 derived from L-proline with (thio)phosphoro(-no)dichlorides 2 give 1,2,3-azaphosphaoxabicyclo[3.3.0] 3 consisting of unequal amounts of diastereoisomers, eight pairs of which have been successfully separated by silica gel column chromatography or recrystallization.
文摘The present paper covers three silabridged hafnocene dichlorides(1, 2 and 3) prepared by sequential reactions of α, ω-dichloropermethyl polysilane with cyclopentadienyl sodium, n-butyl lithium and hafnium tetrachloride. Their structures were characterized by elemental analyses, UV, 1H(13C) NMR and MS. Furthermore the crystal and molecular structures of 1 and 2 were determined by X-ray diffraction method. The crystal of 1 is monoclinic, space group C2/c with a=1. 3401(4), b=0. 9977(3), c = 1. 0922(4) nm; β=94. 07(1)° V=3. 6342 nm3, Z = 2, Dc = 2.155 g·cm-3. The final deviation factor R = 0. 064. The crystal of 2 is monoclinic, space group P21/c with a=0.0847(1), b=1.5181(1), c=2.9824(2) nm; β= 94. 07(1)°? V=3.634 nm3; Dc= l. 805 g·cm-3. The final deviation factor R = 0. 033. The relationship between the silabridged structure and spectral properties is also discussed.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1403300 and 2019YFA0308404)the National Natural Science Foundation of China(Grant Nos.11427902,11991060,12074075,12474165,12274084,and 12241402)+5 种基金Shanghai Municipal Science and Technology Major Project(Grant No.2019SHZDZX01)Shanghai Municipal Natural Science Foundation(Grant No.22ZR1407400)Innovation Program for Quantum Science and Technology(Grant No.2024ZD0300104)Innovation Program of Shanghai Municipal Education Commission(Grant No.2023ZKZD03)Science and Technology Commission of Shanghai Municipality(Grant No.20JC1415900)China Postdoctoral Science Foundation(Grant No.KLH1512149).
文摘Recently,charged solitons have been found in a two-dimensional CoCl_(2)/HOPG system,whose microscopic nature remains to be elusive.In this work,we investigate the charged solitons in monolayer CoCl_(2) using scanning tunneling microscopy(STM)and atomic force microscopy(AFM).Moreover,we study the electrical properties of the charged solitons at zero electric field by measuring local contact potential difference(LCPD)via Kelvin probe force microscopy(KPFM)using the Δf(V)method.The compensation voltage corresponding to the vertex of the parabola is obtained by fitting the quadratic relationship between Δf and sample bias.The results show that,without an external electric field,the solitons behave as negatively charged entities.Meanwhile,the LCPD mapping characterizes the spatial distribution of the potential at the charged solitons,which agrees well with those obtained from STM band bending measurements.
基金funding from the European Research Council (ERC) under the European Union’s (EU’s) Horizon 2020 research and innovation program ERC Starting Grant “INTERCELLMED” (No. 759959)the EU’s Horizon 2020 research and innovation program under grant agreement No. 953121 (FLAMIN-GO)+7 种基金the Associazione Italiana per la Ricerca contro il Cancro (AIRCMFAG-2019No. 22902)the “Tecnopolo per la medicina di precisione” (Tecno Med Puglia)-Regione Puglia: DGR n.2117 of 21/11/2018, B84I18000540002the Italian Ministry of Research (MUR) in the framework of the National Recovery and Resilience Plan (NRRP), “NFFA-DI” Grant (n. B53C22004310006), “I-PHOQS” Grant (n. B53C22001750006) and under the complementary actions to the NRRP, “Fit4MedRob” Grant (PNC0000007, n. B53C22006960001), “ANTHEM” Grant (PNC0000003, n. B53C22006710001), funded by Next Generation EUthe PRIN 2022 (2022CRFNCP_PE11_PRIN2022) funded by European Union-Next Generation EUthe financial support provided under the project “HEALTH-UNORTE: Setting-up biobanks and regenerative medicine strategies to boost research in cardiovascular, musculoskeletal, neurological, oncological, immunological, and infectious diseases” (reference NORTE-01-0145FEDER-000039) funded by the Norte Portugal Regional Coordination and Development Commission (CCDR-N) under the NORTE2020 Programthe AIRC Short-term Fellowship program
文摘Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell cultures.In this study,ratiometric O_(2)-sensing membranes were prepared by electrospinning,an easy,low-cost,scalable,and robust method for fabricating nanofibers.Poly(ε-caprolactone)and poly(dimethyl)siloxane polymers were blended with tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)dichloride,which was used as the O_(2)-sensing probe,and rhodamine B isothiocyanate,which was used as the reference dye.The functionalized scaffolds were morphologically characterized by scanning electron microscopy,and their physicochemical profiles were obtained by Fourier transform infrared spectroscopy,thermogravimetric analysis,and water contact angle measurement.The sensing capabilities were investigated by confocal laser scanning microscopy,performing photobleaching,reversibility,and calibration curve studies toward different dissolved O_(2)(DO)concentrations.Electrospun sensing nanofibers showed a high response to changes in DO concentrations in the physiological-pathological range from 0.5%to 20%and good stability under ratiometric imaging.In addition,the sensing systems were highly biocompatible for cell growth promoting adhesiveness and growth of three cancer cell lines,namely metastatic melanoma cell line SK-MEL2,breast cancer cell line MCF-7,and pancreatic ductal adenocarcinoma cell line Panc-1,thus recreating a suitable biological environment in vitro.These O_(2)-sensing biomaterials can potentially measure alterations in cell metabolism caused by changes in ambient O_(2)content during drug testing/validation and tissue regeneration processes.
基金Supported by Funds of the National Natural Science Foundation of ChinaNo.80112725+1 种基金Administration of Traditional Chinese Medicine of Shaanxi Province of ChinaNo.jc10
文摘AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis.METHODS: The mice were randomly divided into 2 groups(n = 50), control group and model group. The mice in model group were given ethanol(10%) in drinking water after injection of dibutyltin dichloride(DBTC)(8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein( 60 % ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin(FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen typeⅠ(COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1(MMP-1) and tissue inhibitor of metalloproteinases-1(TIMP-1) m RNA in the pancreas was assessed by real time PCR.RESULTS: DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group(P < 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 m RNA in pancreas decreased, but TIMP-1 m RNA increased at model group.CONCLUSION: DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis.
基金Supported by the National Natural Science Foundation of China (20676095)the Program of Introducing Talents of Discipline to Universities (B06006)
文摘Crosslinking treatments for a commercially available aromatic polyamide reverse osmosis membrane were carried out to improve its chlorine resistance.The crosslinking agents including 1,6-hexanediol diglycidyl ether,adipoyl dichloride and hexamethylene diisocyanate ester with long flexible aliphatic chains and high reactivity with N-H groups were used in the experiments.Attenuated total reflective Fourier transform infrared spectra verified the successful preparation of highly crosslinked membranes by crosslinking treatments.It was suggested that the crosslinking agents were connected to membrane surface through the reactions with amine and amide Ⅱ groups,which is confirmed by surface charge measurements.Based on contact angle measurements,crosslinking treatments decreased membrane hydrophilicity by introducing methylene groups to membrane surface.With increasing amount of crosslinking agent molecules connected to membrane surface,the hydrolysis of unconnected functional groups of crosslinking agent produced polar groups and increased membrane hydrophilicity.The highly crosslinked membranes showed higher salt rejections and lower water fluxes as compared with the raw membrane.Since the active sites(N-H groups) vulnerable to free chlorine on membrane surface were eliminated by crosslinking treatments,the chlorine resistances of the highly crosslinked membranes were significantly improved by slighter changes in both water fluxes and salt rejections after chlorination.
文摘An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. Treatment of primary or secondary alcohols with VH gave alkyl formates or alkyl chlorides by depending on the reaction conditions.
基金supported by the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(No.18KJA140002)National Natural Science Foundation of China(Nos.11564040,21763027)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX18_1015)College Students’ Practice Innovation Training Program of Nuist(No.201810300033Z)
文摘Disulfur dichloride is a hazardous substance, which is irritating to the eyes. It is significant to study the physical and dissociation properties under external electric fields. The bond length, energy, dipole moment, orbital energy level distribution, infrared spectra and dissociation properties of disulfur dichloride molecule under different external fields are obtained by using the density functional theory at the B3LYP/6-311++G(d, p) basis set level. In addition, ultraviolet-visible absorption spectra of the molecule in different electric fields are studied with configuration interaction-single excitation(CIS)/6-311++G(d, p) method. According to the results, it has been found that as the electric field exerted along the positive direction of the z-axis increases, the two sulfur-chlorine(S-Cl) bond lengths become longer and tend to break, while the sulfur-sulfur(S-S) bond length becomes shorter and the energy gap decreases. The infrared spectrum and ultraviolet-visible absorption spectra both exhibit red shift under electric field. Moreover, by scanning the potential energy surface of disulfur dichloride about S-Cl bond, the dissociation barrier decreases with the increase of positive electric field. When the external electric field arrives at 0.040 atomic units, the barrier disappears, meaning the dissociation of disulfur dichloride. The present results offer an important reference to further study of disulfur dichloride.
基金Supported by National Institutes of Health Grants,No. NS039041,to Westlund KN and DE19177,to Oz HS
文摘AIM:To analyze gene expression profiles in an experimental pancreatitis and provide functional reversal of hypersensitivity with candidate gene endothelin-1 antagonists.METHODS:Dibutyltin dichloride(DBTC) is a chemical used as a polyvinyl carbonate stabilizer/catalyzer,biocide in agriculture,antifouling agent in paint and fabric.DBTC induces an acute pancreatitis flare through generation of reactive oxygen species.Lewis-inbred rats received a single i.v.injection with either DBTC or vehicle.Spinal cord and dorsal root ganglia(DRG) were taken at the peak of inflammation and processed for transcriptional profiling with a cDNA microarray biased for rat brain-specific genes.In a second study,groups of animals with DBTC-induced pancreatitis were treated with endothelin(ET) receptor antagonists [ET-A(BQ123) and ET-B BQ788)].Spontaneous pain related mechanical and thermal hypersensitivity were measured.Immunohistochemical analysis was performed using anti-ET-A and ET-B antibodies on sections from pancreatic tissues and DRG of the T10-12 spinal segments.RESULTS:Animals developed acute pancreatic inflammation persisting 7-10 d as confirmed by pathological studies(edema in parenchyma,loss of pancreatic architecture and islets,infiltration of inflammatory cells,neutrophil and mononuclear cells,degeneration,vacuolization and necrosis of acinar cells) and the painrelated behaviors(cutaneous secondary mechanical and thermal hypersensitivity).Gene expression profile was different in the spinal cord from animals with pancreatitis compared to the vehicle control group.Over 260 up-regulated and 60 down-regulated unique genes could be classified into 8 functional gene families:circulatory/acute phase/immunomodulatory;extracellular matrix;structural;channel/receptor/transporter;signaling transduction;transcription/translation-related;antioxidants/chaperones/heat shock;pancreatic and other enzymes.ET-1 was among the 52 candidate genes upregulated greater than 2-fold in animals with pancreatic inflammation and visceral pain-related behavior.Treatments with the ET-A(BQ123) and ET-B(BQ-788) antagonists revealed significant protection against inflammatory pain related mechanical and thermal hypersensitivity behaviors in animals with pancreatitis(P < 0.05).Open field spontaneous behavioral activity(at baseline,day 6 and 30 min after drug treatments(BQ123,BQ788) showed overall stable activity levels indicating that the drugs produced no undesirable effects on normal exploratory behaviors,except for a trend toward reduction of the active time and increase in resting time at the highest dose(300 μmol/L).Immunocytochemical localization revealed that expression of ET-A and ET-B receptors increased in DRG from animals with pancreatitis.Endothelin receptor localization was combined in dual staining with neuronal marker NeuN,and glia marker,glial fibrillary acidic protein.ET-A was expressed in the cell bodies and occasional nuclei of DRG neurons in na ve animals.However,phenotypic expression of ET-A receptor was greatly increased in neurons of all sizes in animals with pancreatitis.Similarly,ET-B receptor was localized in neurons and in the satellite glia,as well as in the Schwann cell glial myelin sheaths surrounding the axons passing through the DRG.CONCLUSION:Endothelin-receptor antagonists protect against inflammatory pain responses without interfering with normal exploratory behaviors.Candidate genes can serve as future biomarkers for diagnosis and/or targeted gene therapy.
文摘Bone metastases have a major impact on quality of life and survival of patients with advanced prostate cancer,in the last decade,the development and approval of substances inhibiting the vicious cycle of bone metastases have enabled the reduction of complications caused by bone metastases in patients with castration-resistant prostate cancer.These drugs have raised awareness of the importance of skeletal-related events which in the meantime represent an important end point also in trials using agents not specifically designed for bone lesions.Second-generation antihormona]drugs such as enzalutamide or abiraterone have been shown to have a positive impact on the incidence of skeletal complications and therefore provide an important tool in the armamentarium used for treating bone metastases.Radiopharmaceuticals such as radium-223 dichloride([^223Ra])have been demonstrated not only to reduce skeletal-related events and bone-related pain,but also to prolong overall survival,thereby being the first bone-targeting agent showing a survival benefit.As previous studies have not provided an obvious benefit of bone-targeted lesions in castration-sensitive disease,the use of these agents is not recommended.In oligometastatic prostate cancer,the role of local treatment of metastases using stereotactic radiation or radiosurgery is a matter of intense debates and may play an increasing role in the future.
文摘1,4-Bis(triphenylphosphonium)-2-butene dichloride(BTPBDC) and 1,4-bis(triphenyl phosphonium)-2-butene dithiocyanate (BTPBDT) were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.
文摘Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a novel pre‐oxidation‐pyrolysis process,affording unprecedented dehydrochlorination activity with good durability.The best‐performing system was further modified with different precious metals(Au,Pt,and Ru)to promote the hydrochlorination chemistry between the in‐situ formed hydrogen chloride and acetylene co‐feed.The presence of metal centers intensifies the hydrochlorination activity but weakens the dehydrochlorination ability due to competitive adsorption between the two reactants at the metal sites.Superior coupling performance was achieved over C_(3)N_(4)/AC and single‐atom Au/C_(3)N_(4)/AC catalysts in cascade reactors.Our results strongly suggest that dehydrochlorination is an essential step in the coupling reaction,and the activation of acetylene and ethylene dichloride molecules requires different active sites that should be engineered in future work.
文摘Ab initio study of the equilibrium structure, spectroscopy constants, and anharmonic force field for several isotopomers of germanium dichloride (70GeCl2, 72GECl2, and 76GeCl2) have been carried out at the MP2 and CCSD(T) levels of theory using cc-pVTZ basis set. The cal- culated geometries, rotational constants, vibration-rotation interaction constants, harmonic frequencies, anharmonic constants, quartic and sextic centrifugal distortion constants, cubic and quartic force constants are compared with experimental data. For small mass differences of the Ge isotopes, the isotopic effects for germanium dichloride are much weaker. The agreements are satisfactory for these two methods, but the deviations of CCSD(T) results are slightly larger than that of MP2, because of CCSD(T)'s inadequate treatment of electron correlation in hypervalent Cl atom.
基金This work was also supported by the Core Research for Engineering Innovation KGCX2-203 of the Chinese Academy of Sciences, National Natural Science Foundation of China (No. 20272062) and the "One Hundred Talents" Fund foWen-Hua Sun.
文摘8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.
基金National Natural Science Foundation of China (Project No. 20072033) and Natural Science Foundation of Zhejiang province for financial support.
文摘The intermolecular coupling of a nitro group with a cyano group mediated by a Sm(Hg) amalgam prepared from metal samarium powder and catalytic mercury dichloride was studied.
基金This project of 29504030 was supported by the National Natural Science Foundation of China
文摘Some organogermanium oligomers with different side groups were synthesized via ligand substitution polymerization from I, l-dioxane complex of germanium dichloride with different organolithium compounds. The oligomers were isolated through either precipitation from methanol or extraction using toluene with a yield of no less than 50%. The weight average molecular weight (M-w) of the oligomers is ranging from 1.4 x 10(3) to 5.9 x 10(3) depending on the type and alkyl length of the organolithium compounds used.
文摘Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane (MAO) catalyst system under mild condition. High yield was gained and no other oligmer was detected. It was found that the ratio of AI/Zr is responsible for the selectivity of product.
基金supported by the Key Fund of Education Committee of Hunan Province (06009)Natural Science Fundation of Hunan Province (05JJ40015, 06JJ50022)+1 种基金Science and Technology Fund of Hunan Province (2007FJ4140)Key Subject Fund and Key Lab Fund of Hunan Province
文摘A novel organotin hydration dibenzyltin dichloride has been synthesized and its crystal structure was determined by X-ray diffraction. The crystal belongs to monoclinic, space group Pc with a = 1.1918(5), b = 0.6199(2), c = 1.1074(5)nm, β = 106.899(7)°, V= 0.7828(8)nm3, Z = 2, Dc = 1.654 g/cm3,μ(MoKa) = 19.59 cm^-1, F(000) = 384, R = 0.0564 and RwR = 0.1427. The Sn-C bonds are 0.2140(9) and 0.2152(5) nm, Sn-Cl are 0.2385(4) and 0.2497(3) nm, and Sn-O is 0.2388(7) nm. The tin atom is five-coordinated in a distorted trigonal bipyramidal configuration. The study on the title complex has been performed with quantum chemistry calculation by means of G98W package on the Lanl2dz basis set. The stability of the complex as well as the orbital energies and composition characteristics of some frontier molecular orbitals has been investigated.