The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterize...The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterized by elemental analysis,thermal analysis,IR spectra and single-crystal X-ray structure analysis.The crystal of the Gd(Ⅲ) complex belongs to triclinic system,space group P1 with:a=0.796 25(16) nm,b=0.944 46(19) nm,c=1.262 1(3) nm,α=76.50(3)°,β=84.95(3)°,γ=83.04(3)°,Z=2,V=0.914 4(3) nm3,Dc=2.669 g.cm-1,μ=7.269 mm-1,F(000)=692,and R1=0.033 3,wR2=0.062 3.The crystal structure revealed that compound 1 has a 2D layer structure incorporating 1D Gd-O-Gd double chain,and hydrogen bonding interactions result in the former of 3D supramolecular network structure.CCDC:669079.展开更多
In the past few years, support vector machines (SVMs) have been applied to many fields, such as pattern recognition and data mining, etc. However there still exist some problems to be solved. One of them is that the S...In the past few years, support vector machines (SVMs) have been applied to many fields, such as pattern recognition and data mining, etc. However there still exist some problems to be solved. One of them is that the SVM is very sensitive to outliers or noises because of over-fitting problem. In this paper, a fuzzy support vector regression (FSVR) method is presented to deal with this problem. Strategies based on k nearest neighbor (kNN) and support vector data description (SVDD) are adopted to set the fuzzy membership values of data points in FSVR.The proposed FSVR soft sensor models based on kNN and SVDD are employed to predict the concentration of 4-carboxy-benzaldehyde (4-CBA) in purified terephthalic acid (PTA) oxidation process. Simulation results indicate that the proposed method indeed reduces the effect of outliers and yields higher accuracy.展开更多
C4-dicarboxylate transport proteins of di-azotroph Pseudomonas stutzeri were encoded by dctPQM genes. Nucleotide sequence analysis indicated that dctP, dctQ, and dctM grouped together. Its nucleotide and amino acid se...C4-dicarboxylate transport proteins of di-azotroph Pseudomonas stutzeri were encoded by dctPQM genes. Nucleotide sequence analysis indicated that dctP, dctQ, and dctM grouped together. Its nucleotide and amino acid sequence shared high homology with that of dctP gene en-coding periplasmic C4-dicarboxylate-binding protein and dctQM genes encoding C4-dicarboxylate transport proteins from the free-living nitrogen-fixing Aotobacter vinelandii. Structural analysis showed that DctP of P. stutzeri did not include membrane-spanning regions, and DctQ and DctM contained 5 and 12 transmembrane segments, respectively. The fragment containing the complete dctPQM genes was cloned into the Tn5 transposon region of suicide mobiliza-tion plasmid pSZ21. The resultant plasmid was named pSZY6. By triparental mating, Tn5 transposon carrying the dctPQM genes inserted into the genome of the wild type strain A1501, randomly. The recombinant strain A-142 which harboured an extra copy of dctPQM genes was con-structed and identified by PCR amplification of npt II gene. When A-142 was grown in minimal medium with different concentrations (20, 10 and 5 mmol/L) of C4-dicarboxylates succinate, malate, or fumarate as the sole carbon source, the rate of nitrogen fixation assayed by acetylene reduction was significantly higher than that of the wild-type strain A1501. This result was established that an extra copy of dctPQM genes could increase the activity of nitrogen fixation of P. stutzeri strain A1501.展开更多
It is difficult to treat 2-amino-thiazoline-4-carboxylic acid （ATC） waste liquid effectively at present for its characteristics of high chemical oxygen demand （COD）, high salinity and low biodegradability. In orde...It is difficult to treat 2-amino-thiazoline-4-carboxylic acid （ATC） waste liquid effectively at present for its characteristics of high chemical oxygen demand （COD）, high salinity and low biodegradability. In order to solve this problem, this paper presents several kinds of physical-chemical treatment unit techniques, including acid separation, catalytic oxidation and coagulation. First of all, acid separation was adopted to precipitate relevant organics at isoelectric point. When the temperature and pH value of acid separation were controlled at about 5 ℃ and 2.2 respectively, the COD removal rate could reach 27.600. Secondly, oxidation was used to break chemical constitution of refractory organics. The optimal reaction parameters of catalytic oxidation should be 20 ℃, pH adjusted to 5.0 and [Fe2+] 300 mg/L. Then with 500 H2O2 added and after one-hour reaction, the COD removal rate could achieve about 5200. Finally, coagulation was adopted to remove a portion of refractory organics, and 1500 polymeric molysite flocculant was the best for the coagulation, and the COD removal rate could reach about 1500. Therefore, the proposed feasible process of physical-chemical pretreatment for ATC waste liquid could have about 7000 COD removed in total.展开更多
文摘The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterized by elemental analysis,thermal analysis,IR spectra and single-crystal X-ray structure analysis.The crystal of the Gd(Ⅲ) complex belongs to triclinic system,space group P1 with:a=0.796 25(16) nm,b=0.944 46(19) nm,c=1.262 1(3) nm,α=76.50(3)°,β=84.95(3)°,γ=83.04(3)°,Z=2,V=0.914 4(3) nm3,Dc=2.669 g.cm-1,μ=7.269 mm-1,F(000)=692,and R1=0.033 3,wR2=0.062 3.The crystal structure revealed that compound 1 has a 2D layer structure incorporating 1D Gd-O-Gd double chain,and hydrogen bonding interactions result in the former of 3D supramolecular network structure.CCDC:669079.
基金National Key Technologies Research and Development Program in the 10th five-year plan，国家杰出青年科学基金
文摘In the past few years, support vector machines (SVMs) have been applied to many fields, such as pattern recognition and data mining, etc. However there still exist some problems to be solved. One of them is that the SVM is very sensitive to outliers or noises because of over-fitting problem. In this paper, a fuzzy support vector regression (FSVR) method is presented to deal with this problem. Strategies based on k nearest neighbor (kNN) and support vector data description (SVDD) are adopted to set the fuzzy membership values of data points in FSVR.The proposed FSVR soft sensor models based on kNN and SVDD are employed to predict the concentration of 4-carboxy-benzaldehyde (4-CBA) in purified terephthalic acid (PTA) oxidation process. Simulation results indicate that the proposed method indeed reduces the effect of outliers and yields higher accuracy.
基金supported by the National Basic Research Priorities Programme(Grant No.001CB108904)the National Natural Science Foundation of China(Grant No.39580001).
文摘C4-dicarboxylate transport proteins of di-azotroph Pseudomonas stutzeri were encoded by dctPQM genes. Nucleotide sequence analysis indicated that dctP, dctQ, and dctM grouped together. Its nucleotide and amino acid sequence shared high homology with that of dctP gene en-coding periplasmic C4-dicarboxylate-binding protein and dctQM genes encoding C4-dicarboxylate transport proteins from the free-living nitrogen-fixing Aotobacter vinelandii. Structural analysis showed that DctP of P. stutzeri did not include membrane-spanning regions, and DctQ and DctM contained 5 and 12 transmembrane segments, respectively. The fragment containing the complete dctPQM genes was cloned into the Tn5 transposon region of suicide mobiliza-tion plasmid pSZ21. The resultant plasmid was named pSZY6. By triparental mating, Tn5 transposon carrying the dctPQM genes inserted into the genome of the wild type strain A1501, randomly. The recombinant strain A-142 which harboured an extra copy of dctPQM genes was con-structed and identified by PCR amplification of npt II gene. When A-142 was grown in minimal medium with different concentrations (20, 10 and 5 mmol/L) of C4-dicarboxylates succinate, malate, or fumarate as the sole carbon source, the rate of nitrogen fixation assayed by acetylene reduction was significantly higher than that of the wild-type strain A1501. This result was established that an extra copy of dctPQM genes could increase the activity of nitrogen fixation of P. stutzeri strain A1501.
基金Scientific and Technology InnovationProject of the Higher Education Institutions of Shanxi Province(2020L0598)the Startup Fund of Doctors of Jinzhong University and the Innovation Team Construction Plan of“1331 Project”of Jinzhong University(jzxycxtd2019010)。
文摘It is difficult to treat 2-amino-thiazoline-4-carboxylic acid （ATC） waste liquid effectively at present for its characteristics of high chemical oxygen demand （COD）, high salinity and low biodegradability. In order to solve this problem, this paper presents several kinds of physical-chemical treatment unit techniques, including acid separation, catalytic oxidation and coagulation. First of all, acid separation was adopted to precipitate relevant organics at isoelectric point. When the temperature and pH value of acid separation were controlled at about 5 ℃ and 2.2 respectively, the COD removal rate could reach 27.600. Secondly, oxidation was used to break chemical constitution of refractory organics. The optimal reaction parameters of catalytic oxidation should be 20 ℃, pH adjusted to 5.0 and [Fe2+] 300 mg/L. Then with 500 H2O2 added and after one-hour reaction, the COD removal rate could achieve about 5200. Finally, coagulation was adopted to remove a portion of refractory organics, and 1500 polymeric molysite flocculant was the best for the coagulation, and the COD removal rate could reach about 1500. Therefore, the proposed feasible process of physical-chemical pretreatment for ATC waste liquid could have about 7000 COD removed in total.
