Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutri...Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutritional compounds and functional metabolites is crucial for the development of functional foods from medicinal and dietary plants.Nuclear magnetic resonance(NMR)and mass spectrometry(MS)are indispensable and essential technologies that provide an unsurpassed wealth of untargeted identification,quantitative and qualitative analysis,and structural information in the study of food and plant products.In the past decade,the rapid development of modern analytical technology has led to the emergence of new approaches and strategies for natural products discovery.Especially the application of novel NMRand MS-based identification and dereplication strategies aided by artificial intelligence and machine learning algorithms have brought about a significant shift in the natural products discovery process.These developments and changes in the natural products filed have given us insights into how to accurately target and mining nutritional,functional,and bioactive compounds.Thus,we have summarized recent research on novel NMR and MS based strategies and methods focusing on functional compounds,accurate identification and efficient discovery mainly in medicinal and dietary plants.This review could provide a comprehensive perspective for a better understanding of novel strategies and methods based on NMR and MS technologies,which could provide valuable insights and ideas for functional compounds mining.展开更多
The possible geometries of Fe(HCN)n (n = 1~6) compounds were studied by using + DFT/UB3LYP/6-31G(2df) method. The structure and ground state ...The possible geometries of Fe(HCN)n (n = 1~6) compounds were studied by using + DFT/UB3LYP/6-31G(2df) method. The structure and ground state of each fragmental ion are C∞v (4Σ+ or Σ ), D∞h (4Σg ), D3 (4A1 ), C2 or Td or C3v (4A1), and D3 (4A1 ) or C4 ( A1 ) sequentially 6 + + ′ ′ ′ 2 ′ h v h v with n = 1～5. For the compound Fe(HCN)6 , the possible geometry was not obtained. The + sequential incremental interaction energy (–?(?E)), dissociation energy (?D0), enthalpy (–?(?H)) and Gibbs free energy (–?(?G)), and frequencies for HCN-Fe(HCN)n + -1 were also calculated, and the results are all in good agreement with the experiments. The bond length of Fe–N is lengthened with the increase of cluster size, and the strength of Fe+–N coordination bond varies nonmon- tonically as increasing the number of ligands. The Fe+–N bond of Fe(HCN)2 is the strongest in all + compounds.展开更多
A novel compound [Cl2Bz（3-MeQl） ]（TCNQ） （[Cl2Bz（3-MeQl） ]^＋ = 1-（3,4-dichlo-robenzyl） 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion） has been synthesized by the reaction of [Cl2Bz...A novel compound [Cl2Bz（3-MeQl） ]（TCNQ） （[Cl2Bz（3-MeQl） ]^＋ = 1-（3,4-dichlo-robenzyl） 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion） has been synthesized by the reaction of [Cl2Bz（3-MeQl） ]Br and LiTCNQ,and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic,space group P21/c. The structure analysis shows that the anions are stacked into a column with isolated π-dimers,and there is one type of TCNQ entries（TCNQ^-） ,in agreement with the IR spectra analysis and density functional theory calculations of the compound. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [Cl2Bz（3-MeQl）]＋ cations.展开更多
Sorption enhanced steam methane reforming（SE-SMR） was performed to maximize hydrogen production and contemporary remove COfrom the product stream using bi-functional sorbent-catalyst compounds.Samples were tested at...Sorption enhanced steam methane reforming（SE-SMR） was performed to maximize hydrogen production and contemporary remove COfrom the product stream using bi-functional sorbent-catalyst compounds.Samples were tested at two different scales: micro and laboratory. The CaO amount varied in the CaO-CaAlOsorbent system synthesized by wet mixing(CaO content of 100 wt%, 56 wt%, 30 wt%, or 0 wt% and balance of CaAlO) which were upgraded to bi-functional compounds by impregnation of 3 wt% of Ni. Nitrogen adsorption（BET/BJH）, X-Ray Diffraction（XRD）, Temperature-Programmed Reduction（TPR） and Scanning and Transmission Electronic Microscopy（SEM and TEM, respectively） analyses were performed to characterize structural and textural properties and reducibility of the bi-functional materials and evaluate their catalytic behavior. A fixed sorbent composition CaO-CaAlO(56 wt% of CaO and CaAlObalance), was chosen to study the effect of different weight hourly space times（WHST） and CHstream compositions in SE-SMR activity. Impregnated mayenite at both micro and laboratory scales showed stable Hcontent of almost 74%, with CHconversion of 72% similarly to the values reported by the sample containing 30 wt% of CaO in the post-breakthrough.Sample with 30 wt% of CaO showed promisingly behavior, enhancing Hcontent up to almost 94.5%.When the sorption enhanced reaction is performed roughly 89% of CHconversion is achieved, and after the pre-breakthrough, the catalyst worked at the thermodynamic level. During cycling sorption/regeneration experiments, even if COremoval efficiency slightly decreases, CHconversion and Hyield remain stable.展开更多
Two Co(II)-MOFs with different structures were successfully synthesized under the premise of designing two ligands containing alkynyl functional groups. Complexes 1 ([Co(TEPA)(TPT)2/3]·2DMF·H2O) and 2 ([Co(E...Two Co(II)-MOFs with different structures were successfully synthesized under the premise of designing two ligands containing alkynyl functional groups. Complexes 1 ([Co(TEPA)(TPT)2/3]·2DMF·H2O) and 2 ([Co(EPA)(TPT)]·1.5DMF·1.5H2O) show excellent luminescence properties. Meanwhile, as fluorescent sensors, complexes 1 and 2 exhibit selectivity and sensitivity for Fe3+ with the Ksv of 1.520 ×104 L/mol and 3.543 ×104 L/mol, which can rapidly detect nitroaromatic compounds in methanol and ethanol, especially for 2,4-NPH through fluorescence quenching with high quenching efficiency. In particular, the Ksv value of complexes 1 and 2 towards 2,4-NPH can reach up to 1.627 ×105 L/mol and 9.600 ×104 L/mol, demonstrating that complexes 1 and 2 are good candidates for the identification and detection of Fe3+and nitroaromatic compounds.展开更多
The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were explored.It was found that the phenol-fed system（...The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were explored.It was found that the phenol-fed system（PFS） exhibited stronger degrading abilities and more stable biomass than that of the phenol plus p-cresol-fed system（PCFS）.The microbial community structures were revealed by a modern DNA fingerprint technique,ribosomal intergenic spacer analysis（RISA）.The results indicated that the microbial community of PFS changed obviously when gradually increased phenol concentration,while PCFS showed a little change.16S rRNA sequence analysis of the major bands showed that Alcanivorax sp.genus was predominant species during phenolic compounds degradation.Furthermore,amplified functional DNA restriction analysis（AFDRA） on phenol hydroxylase genes showed that the fingerprints were substantially different in the two systems,and the fingerprints were not the same during the different operational periods.展开更多
With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the o...With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the optimal configuration of improving economy of the system,and then identifying the important nodes.In this strategy,the objectives increase the node importance degree and decrease the active power loss subjected to operational constraints.A compound objective function with weight coefficients is formulated to balance the conflict of the objectives.Then a novel quantum particle swarm optimization based on loop switches hierarchical encoded was employed to address the compound objective reconfiguration problem.Its main contribution is the presentation of the hierarchical encoded scheme which is used to generate the population swarm particles of representing only radial connected solutions.Because the candidate solutions are feasible,the search efficiency would improve dramatically during the optimization process without tedious topology verification.To validate the proposed strategy,simulations are carried out on the test systems.The results are compared with other techniques in order to evaluate the performance of the proposed method.展开更多
The aim of this study was to determine the variation of phenolic compounds in common and tartary buckwheats collected from China, Japan and Korea. Two buckwheat varieties of each country were cultivated using nutrient...The aim of this study was to determine the variation of phenolic compounds in common and tartary buckwheats collected from China, Japan and Korea. Two buckwheat varieties of each country were cultivated using nutrient solution and vermiculite in the greenhouse from February to May, 2012 and harvested at two-week intervals. Phenolics such as chlorogenic acid, C-glycosylflavones (orientin, isoorientin, vitexin, and isovitexin), rutin, and quercetin were quantified using high performance liquid chroma-tography (HPLC). At 17, 29, 44, 58, and 72 days after sowing (DAS), before harvesting each organs, rutin content of cultivars from China and Korea at 17 DAS was the highest (mean 43.63 and 39.95 mg?g–1 DW, respectively) than that of 29 and 44 DAS. However, two varieties from Japan at 44 DAS were documented maximum;whereas, the amount of rutin in “Hokkai T10” harvested at 44 DAS (58.36 mg?g–1 DW) was the highest of all cultivars. Rutin level in the leaves and stems at 72 DAS were comparatively higher than at 58 DAS. The highest of rutin content was found at 72 DAS (73.33 mg?g–1 DW) in “Hokkai T10” leaves followed by “Daegwan No.3-3” (61.13 mg?g–1 DW), “rice tartary” (53.89 mg?g–1 DW). Rutin content of flowers was presented as the highest amount in “Hokkai T10” at 72 DAS (88.3 mg?g–1 DW) was approximately 14-fold higher than that of 58 DAS (6.44 mg?g–1 DW). However, rutin content of flower in “Xiqiao No.2” was 3-fold higher at 72 DAS than at 58 DAS. Rutin and total phenolic compounds content in flowers, leaves, and stems were higher in the order. The content of four C-glycosylflavones in common buckwheat was higher than those in tartary buckwheat, but rutin content which accounted >90% of the total phenolic compounds was higher in tartary buckwheat. The highest amounts of chlorogenic acid and quercetin were measured in the flower of “Xiqiao No.2” (6.85 and 11.69 mg?g–1 DW, respectively). Based on these results, the presence of different phenolic compounds in all the varieties of buckwheat confirmed that it can be regarded as a potent source of functional foods.展开更多
The distribution of Votaw’s λ1（vc） criterion for testing compound symmetryof the covariance matrix of a t-variate Gaussian model has been obtained in terms ofMeijer’s G-function as well as in computable series fo...The distribution of Votaw’s λ1（vc） criterion for testing compound symmetryof the covariance matrix of a t-variate Gaussian model has been obtained in terms ofMeijer’s G-function as well as in computable series form. Special cases of the densityhave also been derived using reduction formulae for G-function.展开更多
Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compoun...Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compound is facilely fabricated via one-pot electrostatic assembly of γ-PGA with cationic ethyl lauroyl arginate(ELA).The functionalized γ-PGA compound(γ-PGA-ELA)ethanol solution can facilely produce colorless and transparent coatings on various inorganic,metal,and polymeric substrates,especially for the lumen of slender catheters(length up to 2 m,and inner diameter down to 1 mm).The functionalized γ-PGA coating presents remarkable antibacterial efficacy in vitro and in vivo.In addition,the γ-PGA compound is used as antibacterial additives of polyolefin via melting extrusion,and the asprepared antibacterial polyolefin demonstrates advantageous antibacterial efficacy.More importantly,the functionalized γ-PGA coating exhibit good hemocompatibility,low cytotoxicity,and satisfactory histocompatibility.The as-proposed γ-PGA compound has a great potential to serve as a safe and multifunctional antibacterial candidate to combat biomedical devices-related infections.展开更多
Inflammatory bowel disease(IBD) is a serious health concern among western societies. The disease is also on the rise in some East Asian countries and in Australia. Health professionals and dietitians around the world ...Inflammatory bowel disease(IBD) is a serious health concern among western societies. The disease is also on the rise in some East Asian countries and in Australia. Health professionals and dietitians around the world are facing an unprecedented challenge to prevent and control the increasing prevalence of IBD. The current therapeutic strategy that includes drugs and biological treatments is inefficient and are associated with adverse health consequences. In this context, the use of natural products is gaining worldwide attention. In vivo studies and clinical evidence suggest that wellplanned dietary regimens with specific nutrients can alleviate gastrointestinal inflammation by modulating inflammatory cytokines, such as tumor necrosis factor α(TNF-α), interleukin 1(IL-1), IL-6, IL-1β, and IL-10. Alternatively, the avoidance of high-fat and highcarbohydrate diets is regarded as an effective tool to eliminate the causes of IBD. Many functional foods and bioactive components have received attention for showing strong therapeutic effects against IBD. Both animal and human studies suggest that bioactive functional foods can ameliorate IBD by downregulating the pro-inflammatory signaling pathways, such as nuclear factor κB, STAT1, STAT6, and pro-inflammatory cytokines, including IL-1β, IL-4, IL-6, COX-2, TNF-α, and interferon γ. Therefore, functional foods and diets have the potential to alleviate IBD by modulating the underlying pathogenic mechanisms. Future comprehensive studies are needed to corroborate the potential roles of functional foods and diets in the prevention and control of IBD.展开更多
We present a comparative study of electronic structure and magnetic properties of Gd5Si4 and Gd5Ge4compounds using first principles full potential linearized augmented plane wave(FP-LAPW) method based on density funct...We present a comparative study of electronic structure and magnetic properties of Gd5Si4 and Gd5Ge4compounds using first principles full potential linearized augmented plane wave(FP-LAPW) method based on density functional theory(DFT) using the WIEN2 k code. The local-spin density approximation with correlation energy(LSDA+U) method has been used as the exchange-correlation potential. The optimized lattice constants are in good agreement with the experimental data. The total and partial density of states(DOS) of Gd5Si4 and Gd5Ge4show the difference in Si 3p-Gd 5d and Ge 4p-Gd 5d hybridization, which have an effective role in indirect exchange interaction.In addition, the magnetic moments of Gd, Si, and Ge atoms and the compounds are calculated to clarify the differences in the magnetic properties of these compounds.展开更多
The intrinsic defect of cadmium vacancy （Vcd） in cadmium telluride （CdTe） has been studied by first-principles cal- culations using potentials with both the screened hybrid functional of Heyd, Scuseria, and Ernzer...The intrinsic defect of cadmium vacancy （Vcd） in cadmium telluride （CdTe） has been studied by first-principles cal- culations using potentials with both the screened hybrid functional of Heyd, Scuseria, and Ernzerhof （HSE） approximation and the generalized gradient approximation of the Perdew-Burke-Ernzerhof form （PBE-GGA）. Both results show that the Ta structure of the Vctl defect for different charges is the most stable structure as compared with the distorted C3v structure with one hole localized at one of the four nearest Te atoms. This indicates that the John-Teller distortion （C3v） structure may be unstable in bulk CdTe crystal. The reason likely lies in the delocalized resonance nature of the t2 state of the Vcd defect. Moreover, the formation energy obtained by the HSE method is about 0.6-0.8 eV larger than that obtained by the PBE method. The transition levels calculated by the PBE method and the HSE method are similar and well consistent with the experimental results.展开更多
Density functional theoretical calculations have been made on the electronic structure of （CH）n（BCO）6-n（n = 0-6） at B3LYP/6- 311 ＋ G（d） level. The nuclear-independent chemical shifts （NICS） values calculate...Density functional theoretical calculations have been made on the electronic structure of （CH）n（BCO）6-n（n = 0-6） at B3LYP/6- 311 ＋ G（d） level. The nuclear-independent chemical shifts （NICS） values calculated using the gauge-including atomic orbitals （GIAO） method were used to assess on the aromaticities of these molecules. The results shows that （CH）n（BCO）6n（n = 0-6） species are aromatic.展开更多
An increasing number of researches have been focused on the relationship between trace elements and animal health. Germanium, as a widely used trace element, exists ubiquitously as germanium or germanium compounds in ...An increasing number of researches have been focused on the relationship between trace elements and animal health. Germanium, as a widely used trace element, exists ubiquitously as germanium or germanium compounds in the living environment of human and animals, and plays important roles in animal production or health. With the intensive study of the physiological function of germanium and its compounds, the effects of germanium on animal physiological functions and health have been gradually confirmed. In this review, we discuss the metabolic distribution, physiological characteristics, biological functions, germanium deficiency and germanium toxicity. Furthermore, we focus on the effects of germanium or germanium compounds on the immunity of animals. It is concluded that germanium or germanium compounds not only has positive effect but also has negative effect on animals. This review aims to provide a reference for the future research or application of the germanium or germanium compounds on animals or human beings.展开更多
An amine capillary column was developed in a fused-silica capillary as stationary phase and applied to separation of basic compounds by capillary electrochromatography (CEC). The functionalized capillary was prepared ...An amine capillary column was developed in a fused-silica capillary as stationary phase and applied to separation of basic compounds by capillary electrochromatography (CEC). The functionalized capillary was prepared by inmobilization of 3-Aminopropyl)triethoxysilane (APTES). The CEC conditions including APTES and buffer concentration, pH and applied voltage were investigated to obtain the optimal CEC system for the separation of three anesthetics as basic test molecules. The capillary column provided an efficiency of up to 20,000 plates/m. Lidocaine, ketamine and xilacine were baseline separated under the running conditions with 10 mM Na2HPO4 pH 9.0 as BGE. The applied voltage was 5 kV temperature was set at 25oC and UV detection was performed. The resolutions were 4.97 and 1.53 for ketamine, lidocaine and xilacine, respectively. The column used in CEC mode showed better separation of the anesthetics compared with those used in the capillary zone mode. The comparison with reversed stationary phases used in HPLC in terms of resolution (Rs), sensitivity (LOD), efficiency (N), precision (RSD), asymmetry (T) was also performed. This study provided an alternative way for the CEC separation of basic compounds and demonstrated the improvement in the chromatographic parameters.展开更多
Bond dissociation energies for the removal of nitrogen dioxide group in some nitroalkane energetic materials have been calculated by using the three hybrid density functional theory （DFT） methods B3LYP, B3PW91 and B...Bond dissociation energies for the removal of nitrogen dioxide group in some nitroalkane energetic materials have been calculated by using the three hybrid density functional theory （DFT） methods B3LYP, B3PW91 and B3P86 with 6-31g^＊＊ and 6-311g^＊＊ basis sets. The computed BDEs have been compared with the available experimental results. It is found that the B3P86 method with 6-31g^＊＊ and 6-311g^＊＊ basis sets can obtain satisfactory bond dissociation energies （BDEs）, which are in extraordinary agreement with the experimental data. Considering the smaller mean absolute deviation and maximum difference, the reliable B3P86/6-311g^＊＊ method was recommended to compute the BDEs for the removal of nitrogen dioxide group in the nitroalkane energetic materials. Using the method, the BDEs of 8 other nitroalkane energetic materials have been calculated and the maximum difference from experimental value is 1.76 kcal.mo1^-1 （for the BDE of tC4Hg-NOz）, which further proves the reliability of B3P86/6-311g^＊＊ method. In addition, it is noted that the BDEs of C-NO2 bond change slightly for main chain nitroalkane compounds with the maximum difference of only 3.43 kcal mo1^-1.展开更多
The electronic band structures of periodic models for S^H compounds are investigated by the density functional theory. Our results show that the Si H compound changes from indirect-gap semiconductor to direct-gap semi...The electronic band structures of periodic models for S^H compounds are investigated by the density functional theory. Our results show that the Si H compound changes from indirect-gap semiconductor to direct-gap semiconductor with the increase of H content. The density of states, the partial density of states and the atomic charge population are examined in detail to explore the origin of this phenomenon. It is found that the Si-Si bonds are affected by H atoms, which results in the electronic band transformation from indirect gap to direct gap. This is confirmed by the nearest neighbour semi-empirical tight-binding （TB） theory.展开更多
基金financially supported by the National Key R&D Program of China(2022YFF1100301)Major Science and Technology Project of Henan Province(231100310200)+1 种基金National Natural Science Foundation of China(32370426)Yunnan Province Science and Technology Department(202305AH340005),and Dr Plant。
文摘Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutritional compounds and functional metabolites is crucial for the development of functional foods from medicinal and dietary plants.Nuclear magnetic resonance(NMR)and mass spectrometry(MS)are indispensable and essential technologies that provide an unsurpassed wealth of untargeted identification,quantitative and qualitative analysis,and structural information in the study of food and plant products.In the past decade,the rapid development of modern analytical technology has led to the emergence of new approaches and strategies for natural products discovery.Especially the application of novel NMRand MS-based identification and dereplication strategies aided by artificial intelligence and machine learning algorithms have brought about a significant shift in the natural products discovery process.These developments and changes in the natural products filed have given us insights into how to accurately target and mining nutritional,functional,and bioactive compounds.Thus,we have summarized recent research on novel NMR and MS based strategies and methods focusing on functional compounds,accurate identification and efficient discovery mainly in medicinal and dietary plants.This review could provide a comprehensive perspective for a better understanding of novel strategies and methods based on NMR and MS technologies,which could provide valuable insights and ideas for functional compounds mining.
基金This research was supported by the National Natural Science Foundation of China (20273013 20303002)+1 种基金 the Key Foundation of Fujian Province (K02012) the Foundation of State Key Laboratory of Structural Chemistry (020051) and of Fuzhou University
文摘The possible geometries of Fe(HCN)n (n = 1~6) compounds were studied by using + DFT/UB3LYP/6-31G(2df) method. The structure and ground state of each fragmental ion are C∞v (4Σ+ or Σ ), D∞h (4Σg ), D3 (4A1 ), C2 or Td or C3v (4A1), and D3 (4A1 ) or C4 ( A1 ) sequentially 6 + + ′ ′ ′ 2 ′ h v h v with n = 1～5. For the compound Fe(HCN)6 , the possible geometry was not obtained. The + sequential incremental interaction energy (–?(?E)), dissociation energy (?D0), enthalpy (–?(?H)) and Gibbs free energy (–?(?G)), and frequencies for HCN-Fe(HCN)n + -1 were also calculated, and the results are all in good agreement with the experiments. The bond length of Fe–N is lengthened with the increase of cluster size, and the strength of Fe+–N coordination bond varies nonmon- tonically as increasing the number of ligands. The Fe+–N bond of Fe(HCN)2 is the strongest in all + compounds.
基金Supported by the National Natural Science Foundation of China (Nos.20771006 and 20901004)
文摘A novel compound [Cl2Bz（3-MeQl） ]（TCNQ） （[Cl2Bz（3-MeQl） ]^＋ = 1-（3,4-dichlo-robenzyl） 3-methlquinoline cation,TCNQ-= 7,7,8,8-tetracyanoquinodimethanide anion） has been synthesized by the reaction of [Cl2Bz（3-MeQl） ]Br and LiTCNQ,and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic,space group P21/c. The structure analysis shows that the anions are stacked into a column with isolated π-dimers,and there is one type of TCNQ entries（TCNQ^-） ,in agreement with the IR spectra analysis and density functional theory calculations of the compound. The most prominent structural features are the completely segregated stacking columns of the TCNQ- anions and [Cl2Bz（3-MeQl）]＋ cations.
基金The financial support of European Contract 299732 UNIfHY(UNIQUE For HYdrogen production, funded by FCH-JU under the topic SP1-JTI-FCH.2011.2.3: Biomass-toHydrogen thermal conversion processes)
文摘Sorption enhanced steam methane reforming（SE-SMR） was performed to maximize hydrogen production and contemporary remove COfrom the product stream using bi-functional sorbent-catalyst compounds.Samples were tested at two different scales: micro and laboratory. The CaO amount varied in the CaO-CaAlOsorbent system synthesized by wet mixing(CaO content of 100 wt%, 56 wt%, 30 wt%, or 0 wt% and balance of CaAlO) which were upgraded to bi-functional compounds by impregnation of 3 wt% of Ni. Nitrogen adsorption（BET/BJH）, X-Ray Diffraction（XRD）, Temperature-Programmed Reduction（TPR） and Scanning and Transmission Electronic Microscopy（SEM and TEM, respectively） analyses were performed to characterize structural and textural properties and reducibility of the bi-functional materials and evaluate their catalytic behavior. A fixed sorbent composition CaO-CaAlO(56 wt% of CaO and CaAlObalance), was chosen to study the effect of different weight hourly space times（WHST） and CHstream compositions in SE-SMR activity. Impregnated mayenite at both micro and laboratory scales showed stable Hcontent of almost 74%, with CHconversion of 72% similarly to the values reported by the sample containing 30 wt% of CaO in the post-breakthrough.Sample with 30 wt% of CaO showed promisingly behavior, enhancing Hcontent up to almost 94.5%.When the sorption enhanced reaction is performed roughly 89% of CHconversion is achieved, and after the pre-breakthrough, the catalyst worked at the thermodynamic level. During cycling sorption/regeneration experiments, even if COremoval efficiency slightly decreases, CHconversion and Hyield remain stable.
基金supported by the National Natural Science Foundation of China(NSFC, No. 21771191)the Taishan Scholar Foundation(No. ts201511019)+1 种基金the Shandong Natural Science Fund (No.ZR2017QB012)the Fundamental Research Funds for the Central Universities(Nos.16CX05015A,18CX06003A,YCX2018071)
文摘Two Co(II)-MOFs with different structures were successfully synthesized under the premise of designing two ligands containing alkynyl functional groups. Complexes 1 ([Co(TEPA)(TPT)2/3]·2DMF·H2O) and 2 ([Co(EPA)(TPT)]·1.5DMF·1.5H2O) show excellent luminescence properties. Meanwhile, as fluorescent sensors, complexes 1 and 2 exhibit selectivity and sensitivity for Fe3+ with the Ksv of 1.520 ×104 L/mol and 3.543 ×104 L/mol, which can rapidly detect nitroaromatic compounds in methanol and ethanol, especially for 2,4-NPH through fluorescence quenching with high quenching efficiency. In particular, the Ksv value of complexes 1 and 2 towards 2,4-NPH can reach up to 1.627 ×105 L/mol and 9.600 ×104 L/mol, demonstrating that complexes 1 and 2 are good candidates for the identification and detection of Fe3+and nitroaromatic compounds.
基金supported by the National Natural Science Foundation of China (No. 50608011)
文摘The changes of microbial community structures and functional genes during the biodegradation of single phenol and phenol plus p-cresol under high salt condition were explored.It was found that the phenol-fed system（PFS） exhibited stronger degrading abilities and more stable biomass than that of the phenol plus p-cresol-fed system（PCFS）.The microbial community structures were revealed by a modern DNA fingerprint technique,ribosomal intergenic spacer analysis（RISA）.The results indicated that the microbial community of PFS changed obviously when gradually increased phenol concentration,while PCFS showed a little change.16S rRNA sequence analysis of the major bands showed that Alcanivorax sp.genus was predominant species during phenolic compounds degradation.Furthermore,amplified functional DNA restriction analysis（AFDRA） on phenol hydroxylase genes showed that the fingerprints were substantially different in the two systems,and the fingerprints were not the same during the different operational periods.
基金Project(61102039)supported by the National Natural Science Foundation of ChinaProject(2014AA052600)supported by National Hi-tech Research and Development Plan,China
文摘With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the optimal configuration of improving economy of the system,and then identifying the important nodes.In this strategy,the objectives increase the node importance degree and decrease the active power loss subjected to operational constraints.A compound objective function with weight coefficients is formulated to balance the conflict of the objectives.Then a novel quantum particle swarm optimization based on loop switches hierarchical encoded was employed to address the compound objective reconfiguration problem.Its main contribution is the presentation of the hierarchical encoded scheme which is used to generate the population swarm particles of representing only radial connected solutions.Because the candidate solutions are feasible,the search efficiency would improve dramatically during the optimization process without tedious topology verification.To validate the proposed strategy,simulations are carried out on the test systems.The results are compared with other techniques in order to evaluate the performance of the proposed method.
文摘The aim of this study was to determine the variation of phenolic compounds in common and tartary buckwheats collected from China, Japan and Korea. Two buckwheat varieties of each country were cultivated using nutrient solution and vermiculite in the greenhouse from February to May, 2012 and harvested at two-week intervals. Phenolics such as chlorogenic acid, C-glycosylflavones (orientin, isoorientin, vitexin, and isovitexin), rutin, and quercetin were quantified using high performance liquid chroma-tography (HPLC). At 17, 29, 44, 58, and 72 days after sowing (DAS), before harvesting each organs, rutin content of cultivars from China and Korea at 17 DAS was the highest (mean 43.63 and 39.95 mg?g–1 DW, respectively) than that of 29 and 44 DAS. However, two varieties from Japan at 44 DAS were documented maximum;whereas, the amount of rutin in “Hokkai T10” harvested at 44 DAS (58.36 mg?g–1 DW) was the highest of all cultivars. Rutin level in the leaves and stems at 72 DAS were comparatively higher than at 58 DAS. The highest of rutin content was found at 72 DAS (73.33 mg?g–1 DW) in “Hokkai T10” leaves followed by “Daegwan No.3-3” (61.13 mg?g–1 DW), “rice tartary” (53.89 mg?g–1 DW). Rutin content of flowers was presented as the highest amount in “Hokkai T10” at 72 DAS (88.3 mg?g–1 DW) was approximately 14-fold higher than that of 58 DAS (6.44 mg?g–1 DW). However, rutin content of flower in “Xiqiao No.2” was 3-fold higher at 72 DAS than at 58 DAS. Rutin and total phenolic compounds content in flowers, leaves, and stems were higher in the order. The content of four C-glycosylflavones in common buckwheat was higher than those in tartary buckwheat, but rutin content which accounted >90% of the total phenolic compounds was higher in tartary buckwheat. The highest amounts of chlorogenic acid and quercetin were measured in the flower of “Xiqiao No.2” (6.85 and 11.69 mg?g–1 DW, respectively). Based on these results, the presence of different phenolic compounds in all the varieties of buckwheat confirmed that it can be regarded as a potent source of functional foods.
文摘The distribution of Votaw’s λ1（vc） criterion for testing compound symmetryof the covariance matrix of a t-variate Gaussian model has been obtained in terms ofMeijer’s G-function as well as in computable series form. Special cases of the densityhave also been derived using reduction formulae for G-function.
基金financially supported by the National Natural Science Foundation of China(Nos.51973221 and 51873213)the Youth Innovation Promotion Association of CAS(No.2017269)+1 种基金the Major Science and Technology Innovation Project of Shandong Province(No.2019JZZY011105)the High-Tech Research&Development Program of CAS-WEGO Group。
文摘Poly(γ-glutamic acid)(γ-PGA)has been found widespread applications in biomedical field because of its excellent water solubility,biocompatibility,and bioactivity.Herein,a water-insoluble γ-PGA antibacterial compound is facilely fabricated via one-pot electrostatic assembly of γ-PGA with cationic ethyl lauroyl arginate(ELA).The functionalized γ-PGA compound(γ-PGA-ELA)ethanol solution can facilely produce colorless and transparent coatings on various inorganic,metal,and polymeric substrates,especially for the lumen of slender catheters(length up to 2 m,and inner diameter down to 1 mm).The functionalized γ-PGA coating presents remarkable antibacterial efficacy in vitro and in vivo.In addition,the γ-PGA compound is used as antibacterial additives of polyolefin via melting extrusion,and the asprepared antibacterial polyolefin demonstrates advantageous antibacterial efficacy.More importantly,the functionalized γ-PGA coating exhibit good hemocompatibility,low cytotoxicity,and satisfactory histocompatibility.The as-proposed γ-PGA compound has a great potential to serve as a safe and multifunctional antibacterial candidate to combat biomedical devices-related infections.
基金supported by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through the High Value-added Food Technology Development Program, funded by the Ministry of Agriculture, Food and Rural Affairs (MAFRA 117073-3)
文摘Inflammatory bowel disease(IBD) is a serious health concern among western societies. The disease is also on the rise in some East Asian countries and in Australia. Health professionals and dietitians around the world are facing an unprecedented challenge to prevent and control the increasing prevalence of IBD. The current therapeutic strategy that includes drugs and biological treatments is inefficient and are associated with adverse health consequences. In this context, the use of natural products is gaining worldwide attention. In vivo studies and clinical evidence suggest that wellplanned dietary regimens with specific nutrients can alleviate gastrointestinal inflammation by modulating inflammatory cytokines, such as tumor necrosis factor α(TNF-α), interleukin 1(IL-1), IL-6, IL-1β, and IL-10. Alternatively, the avoidance of high-fat and highcarbohydrate diets is regarded as an effective tool to eliminate the causes of IBD. Many functional foods and bioactive components have received attention for showing strong therapeutic effects against IBD. Both animal and human studies suggest that bioactive functional foods can ameliorate IBD by downregulating the pro-inflammatory signaling pathways, such as nuclear factor κB, STAT1, STAT6, and pro-inflammatory cytokines, including IL-1β, IL-4, IL-6, COX-2, TNF-α, and interferon γ. Therefore, functional foods and diets have the potential to alleviate IBD by modulating the underlying pathogenic mechanisms. Future comprehensive studies are needed to corroborate the potential roles of functional foods and diets in the prevention and control of IBD.
文摘We present a comparative study of electronic structure and magnetic properties of Gd5Si4 and Gd5Ge4compounds using first principles full potential linearized augmented plane wave(FP-LAPW) method based on density functional theory(DFT) using the WIEN2 k code. The local-spin density approximation with correlation energy(LSDA+U) method has been used as the exchange-correlation potential. The optimized lattice constants are in good agreement with the experimental data. The total and partial density of states(DOS) of Gd5Si4 and Gd5Ge4show the difference in Si 3p-Gd 5d and Ge 4p-Gd 5d hybridization, which have an effective role in indirect exchange interaction.In addition, the magnetic moments of Gd, Si, and Ge atoms and the compounds are calculated to clarify the differences in the magnetic properties of these compounds.
基金supported by the National Natural Science Foundation of China(Grant No.A050506)the Innovation Program of Shanghai Municipal Education Commission,China(Grant No.12ZZ096)+1 种基金the Shanghai Leading Academic Disciplines,China(Grant No.S30107)the Science and Technology Commissionof Shanghai,China(Grant No.11530500200)
文摘The intrinsic defect of cadmium vacancy （Vcd） in cadmium telluride （CdTe） has been studied by first-principles cal- culations using potentials with both the screened hybrid functional of Heyd, Scuseria, and Ernzerhof （HSE） approximation and the generalized gradient approximation of the Perdew-Burke-Ernzerhof form （PBE-GGA）. Both results show that the Ta structure of the Vctl defect for different charges is the most stable structure as compared with the distorted C3v structure with one hole localized at one of the four nearest Te atoms. This indicates that the John-Teller distortion （C3v） structure may be unstable in bulk CdTe crystal. The reason likely lies in the delocalized resonance nature of the t2 state of the Vcd defect. Moreover, the formation energy obtained by the HSE method is about 0.6-0.8 eV larger than that obtained by the PBE method. The transition levels calculated by the PBE method and the HSE method are similar and well consistent with the experimental results.
文摘Density functional theoretical calculations have been made on the electronic structure of （CH）n（BCO）6-n（n = 0-6） at B3LYP/6- 311 ＋ G（d） level. The nuclear-independent chemical shifts （NICS） values calculated using the gauge-including atomic orbitals （GIAO） method were used to assess on the aromaticities of these molecules. The results shows that （CH）n（BCO）6n（n = 0-6） species are aromatic.
文摘An increasing number of researches have been focused on the relationship between trace elements and animal health. Germanium, as a widely used trace element, exists ubiquitously as germanium or germanium compounds in the living environment of human and animals, and plays important roles in animal production or health. With the intensive study of the physiological function of germanium and its compounds, the effects of germanium on animal physiological functions and health have been gradually confirmed. In this review, we discuss the metabolic distribution, physiological characteristics, biological functions, germanium deficiency and germanium toxicity. Furthermore, we focus on the effects of germanium or germanium compounds on the immunity of animals. It is concluded that germanium or germanium compounds not only has positive effect but also has negative effect on animals. This review aims to provide a reference for the future research or application of the germanium or germanium compounds on animals or human beings.
文摘An amine capillary column was developed in a fused-silica capillary as stationary phase and applied to separation of basic compounds by capillary electrochromatography (CEC). The functionalized capillary was prepared by inmobilization of 3-Aminopropyl)triethoxysilane (APTES). The CEC conditions including APTES and buffer concentration, pH and applied voltage were investigated to obtain the optimal CEC system for the separation of three anesthetics as basic test molecules. The capillary column provided an efficiency of up to 20,000 plates/m. Lidocaine, ketamine and xilacine were baseline separated under the running conditions with 10 mM Na2HPO4 pH 9.0 as BGE. The applied voltage was 5 kV temperature was set at 25oC and UV detection was performed. The resolutions were 4.97 and 1.53 for ketamine, lidocaine and xilacine, respectively. The column used in CEC mode showed better separation of the anesthetics compared with those used in the capillary zone mode. The comparison with reversed stationary phases used in HPLC in terms of resolution (Rs), sensitivity (LOD), efficiency (N), precision (RSD), asymmetry (T) was also performed. This study provided an alternative way for the CEC separation of basic compounds and demonstrated the improvement in the chromatographic parameters.
基金The project was supported by the National Natural Science Foundation of China (No. 10574096 and 10676025)
文摘Bond dissociation energies for the removal of nitrogen dioxide group in some nitroalkane energetic materials have been calculated by using the three hybrid density functional theory （DFT） methods B3LYP, B3PW91 and B3P86 with 6-31g^＊＊ and 6-311g^＊＊ basis sets. The computed BDEs have been compared with the available experimental results. It is found that the B3P86 method with 6-31g^＊＊ and 6-311g^＊＊ basis sets can obtain satisfactory bond dissociation energies （BDEs）, which are in extraordinary agreement with the experimental data. Considering the smaller mean absolute deviation and maximum difference, the reliable B3P86/6-311g^＊＊ method was recommended to compute the BDEs for the removal of nitrogen dioxide group in the nitroalkane energetic materials. Using the method, the BDEs of 8 other nitroalkane energetic materials have been calculated and the maximum difference from experimental value is 1.76 kcal.mo1^-1 （for the BDE of tC4Hg-NOz）, which further proves the reliability of B3P86/6-311g^＊＊ method. In addition, it is noted that the BDEs of C-NO2 bond change slightly for main chain nitroalkane compounds with the maximum difference of only 3.43 kcal mo1^-1.
基金supported by the National Natural Science Foundation of China (Grant No. 50775101)the New Century Excellent Talents (Grant No. NCET-04-0515)+2 种基金the Jiangsu Provincial Science and Technology Supporting Project,China (Grant No. BE2008030)Qing Lan Project (2008-04)Jiangsu University Natural Science Foundation of China (Grant No. 07KJB430023)
文摘The electronic band structures of periodic models for S^H compounds are investigated by the density functional theory. Our results show that the Si H compound changes from indirect-gap semiconductor to direct-gap semiconductor with the increase of H content. The density of states, the partial density of states and the atomic charge population are examined in detail to explore the origin of this phenomenon. It is found that the Si-Si bonds are affected by H atoms, which results in the electronic band transformation from indirect gap to direct gap. This is confirmed by the nearest neighbour semi-empirical tight-binding （TB） theory.
