Nitric oxide(NO)is a gaseous molecule produced by 3 different NO synthase(NOS)isoforms:Neural/brain NOS(nNOS/bNOS,type 1),endothelial NOS(eNOS,type 3)and inducible NOS(type 2).Type 1 and 3 NOS are constitutively expre...Nitric oxide(NO)is a gaseous molecule produced by 3 different NO synthase(NOS)isoforms:Neural/brain NOS(nNOS/bNOS,type 1),endothelial NOS(eNOS,type 3)and inducible NOS(type 2).Type 1 and 3 NOS are constitutively expressed.NO can serve different purposes:As a vasoactive molecule,as a neurotransmitter or as an immunomodulator.It plays a key role in cerebral ischemia/reperfusion injury(CIRI).Hypoxic episodes simulate the production of oxygen free radicals,leading to mitochondrial and phospholipid damage.Upon reperfusion,increased levels of oxygen trigger oxide synthases;whose products are associated with neuronal damage by promoting lipid peroxidation,nitrosylation and excitotoxicity.Molecular pathways in CIRI can be altered by NOS.Neuroprotective effects are observed with eNOS activity.While nNOS interplay is prone to endothelial inflammation,oxidative stress and apoptosis.Therefore,nNOS appears to be detrimental.The interaction between NO and other free radicals develops peroxynitrite;which is a cytotoxic agent.It plays a main role in the likelihood of hemorrhagic events by tissue plasminogen activator(t-PA).Peroxynitrite scavengers are currently being studied as potential targets to prevent hemorrhagic transformation in CIRI.展开更多
ε-Caprolactam（CL or CPL） is one of the most important intermediates used in polymer industry for the production of several million tons of nylon-6 every year^[1]. All current commercial processes for the production...ε-Caprolactam（CL or CPL） is one of the most important intermediates used in polymer industry for the production of several million tons of nylon-6 every year^[1]. All current commercial processes for the production of caprolactam are based on either benzene or tolueneI21. Caprolactam is synthesized by the Beckmann rearrangement of cyclohexanone oxime with fuming sulfuric acid or sulfuric acid as the reaction medium, and cyclohexanone oxime is produced by the reaction between cyclohexanone and hydro- xylamine（only one exception is the Toray PNC process）.展开更多
Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying t...Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.展开更多
Ionization and dissociation of nitrosyl chloride CINO were studied using femtosecond laser mass spectra technique. Strong fragmental ions NO^＋ and Cl^＋ were observed with the laser intensity varied from 3.2× 10...Ionization and dissociation of nitrosyl chloride CINO were studied using femtosecond laser mass spectra technique. Strong fragmental ions NO^＋ and Cl^＋ were observed with the laser intensity varied from 3.2× 10^14 to 2.5×10^15 W/cm^2. These fragmental ions were attributed to the direct dissociation of the parent ions. Electronic structure calculations were also carried out with Hartree-Fock, density functional and correlated levels of theory to understand the possible fragmentation pathways. The very low N-Cl bond energy in the parent ion of nitrosyl chloride is a clear reason for the absence of CINO^＋ and CIN^＋ ion peaks from the femtosecond laser mass spectrum.展开更多
Tris)(η 5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosyl cluster was obtained from the reaction of cyclopentadienyl dicarbonyliron dimer with nitrogen monoxide in xylene. The cluster was characterized by elemental a...Tris)(η 5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosyl cluster was obtained from the reaction of cyclopentadienyl dicarbonyliron dimer with nitrogen monoxide in xylene. The cluster was characterized by elemental analyses, IR, MS and 1H NMR. The crystal structure of [(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8O was determined by X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma, a=9.053(2), 6=10.545(2), c=22.525(4) A, V=2150.3(7) A3, Z=4,Dc=1.68 g.cm-3; structure solution and refinement based on 1141 reflections with I > 3.0 (I) (MoKa, A=0.71073 A) converged at R=0.0540. The infrared absorption band at 1325 cm-1 of the μ3-NO in the cluster, which is red shifted, shows that μ3-NO is activated.展开更多
Sodium nitrosylcarbonyliron reacts with methylcyclopentadienylcarbonylmetal（Mo orW）chloride in CHOH/THF at room temperature to give CpMo（CO）NO（1a）(Cp=η-CHCH)or CpW（CO）NO（1b）,[CpMo（CO）]（2a）or[CpW（CO）]...Sodium nitrosylcarbonyliron reacts with methylcyclopentadienylcarbonylmetal（Mo orW）chloride in CHOH/THF at room temperature to give CpMo（CO）NO（1a）(Cp=η-CHCH)or CpW（CO）NO（1b）,[CpMo（CO）]（2a）or[CpW（CO）]（2b）,and CpMo（μ3-NH）(μ2-NO)-（μ2-CO）Fe（CO）（3a）or CpW（μ3-NH）(μ2-NO)（μ2-CO）Fe（CO）（3b）,respectively.Complexes1a,1b,3a and 3b were analyzed by IR,NMR,MS and elemental analyses,and the crystalstructures of 1b,3a and 3b were determined by X-ray diffraction method.The new clusters 3aand 3b have μ3-NH ligands which were formed by redaction of NO in the synthetic reactions.展开更多
文摘Nitric oxide(NO)is a gaseous molecule produced by 3 different NO synthase(NOS)isoforms:Neural/brain NOS(nNOS/bNOS,type 1),endothelial NOS(eNOS,type 3)and inducible NOS(type 2).Type 1 and 3 NOS are constitutively expressed.NO can serve different purposes:As a vasoactive molecule,as a neurotransmitter or as an immunomodulator.It plays a key role in cerebral ischemia/reperfusion injury(CIRI).Hypoxic episodes simulate the production of oxygen free radicals,leading to mitochondrial and phospholipid damage.Upon reperfusion,increased levels of oxygen trigger oxide synthases;whose products are associated with neuronal damage by promoting lipid peroxidation,nitrosylation and excitotoxicity.Molecular pathways in CIRI can be altered by NOS.Neuroprotective effects are observed with eNOS activity.While nNOS interplay is prone to endothelial inflammation,oxidative stress and apoptosis.Therefore,nNOS appears to be detrimental.The interaction between NO and other free radicals develops peroxynitrite;which is a cytotoxic agent.It plays a main role in the likelihood of hemorrhagic events by tissue plasminogen activator(t-PA).Peroxynitrite scavengers are currently being studied as potential targets to prevent hemorrhagic transformation in CIRI.
基金Supported by the National Natural Science Foundation of China(Nos 20233040 and 20572021)
文摘ε-Caprolactam（CL or CPL） is one of the most important intermediates used in polymer industry for the production of several million tons of nylon-6 every year^[1]. All current commercial processes for the production of caprolactam are based on either benzene or tolueneI21. Caprolactam is synthesized by the Beckmann rearrangement of cyclohexanone oxime with fuming sulfuric acid or sulfuric acid as the reaction medium, and cyclohexanone oxime is produced by the reaction between cyclohexanone and hydro- xylamine（only one exception is the Toray PNC process）.
基金Project(22178392)supported by the National Natural Science Foundation of China。
文摘Preparation of high purity ruthenium nitrosyl nitrate using spent Ru-Zn/ZrO_(2)catalyst was studied,including melting and leaching to obtain potassium ruthenate solution,reduction,dissolving,concentrating and drying to obtain ruthenium trichloride,nitrosation and hydrolysis to obtain ruthenium nitrosyl hydroxide,removing of K^(+)and Cl^(-),and neutralization with nitric acid.The effects of temperature,concentration,time and pH on the yield and purity of intermediates and final product were studied,and the optimum process conditions were obtained.The yield of ruthenium nitrosyl nitrate is 92%,the content of ruthenium in high purity product is 32.16%,and the content of Cl^(-)and K^(+)are much less than 0.005%.The reaction kinetics of ruthenium nitrosyl chloride to ruthenium nitrosyl hydroxide was studied.The reaction orders of Ru(NO)Cl_(3)at 40,55 and 70℃are 0.39,0.37 and 0.39,respectively,while those of KOH are 0.16,0.15 and 0.17,respectively.The activation energy is-2.33 k J/mol.
基金Project supported by the Hundred Talent Fund of Chinese Academy of Sciences and the National Natural Science Foundation of China （Nos. 20477047, 20473094）.
文摘Ionization and dissociation of nitrosyl chloride CINO were studied using femtosecond laser mass spectra technique. Strong fragmental ions NO^＋ and Cl^＋ were observed with the laser intensity varied from 3.2× 10^14 to 2.5×10^15 W/cm^2. These fragmental ions were attributed to the direct dissociation of the parent ions. Electronic structure calculations were also carried out with Hartree-Fock, density functional and correlated levels of theory to understand the possible fragmentation pathways. The very low N-Cl bond energy in the parent ion of nitrosyl chloride is a clear reason for the absence of CINO^＋ and CIN^＋ ion peaks from the femtosecond laser mass spectrum.
文摘Tris)(η 5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosyl cluster was obtained from the reaction of cyclopentadienyl dicarbonyliron dimer with nitrogen monoxide in xylene. The cluster was characterized by elemental analyses, IR, MS and 1H NMR. The crystal structure of [(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8O was determined by X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma, a=9.053(2), 6=10.545(2), c=22.525(4) A, V=2150.3(7) A3, Z=4,Dc=1.68 g.cm-3; structure solution and refinement based on 1141 reflections with I > 3.0 (I) (MoKa, A=0.71073 A) converged at R=0.0540. The infrared absorption band at 1325 cm-1 of the μ3-NO in the cluster, which is red shifted, shows that μ3-NO is activated.
文摘Sodium nitrosylcarbonyliron reacts with methylcyclopentadienylcarbonylmetal（Mo orW）chloride in CHOH/THF at room temperature to give CpMo（CO）NO（1a）(Cp=η-CHCH)or CpW（CO）NO（1b）,[CpMo（CO）]（2a）or[CpW（CO）]（2b）,and CpMo（μ3-NH）(μ2-NO)-（μ2-CO）Fe（CO）（3a）or CpW（μ3-NH）(μ2-NO)（μ2-CO）Fe（CO）（3b）,respectively.Complexes1a,1b,3a and 3b were analyzed by IR,NMR,MS and elemental analyses,and the crystalstructures of 1b,3a and 3b were determined by X-ray diffraction method.The new clusters 3aand 3b have μ3-NH ligands which were formed by redaction of NO in the synthetic reactions.
