期刊：
Chemometrics and Intelligent Laboratory Systems,2023年234:104756 ISSN：0169-7439
通讯作者：
Xin Huang
作者机构：
[Huang, Xin] Hunan City Univ, Management Sch, Yiyang 413000, Peoples R China.;[Xia, Li] Hunan City Univ, Sch Chem & Environm Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Xin Huang] M;Management School, Hunan City University, Yiyang, 413000, PR China
关键词：
Iterative distance correlation;Near-infrared spectroscopy;Partial least squares;Wavelength interval selection
摘要：
Wavelength selection is a fundamental and critical step in near infrared spectral analysis, which can improve the prediction performance and enhance the interpretability of the model. Motivated by the appealing properties of the distance correlation, a novel wavelength interval selection algorithm, named iterative distance correlation combined with PLS regression (IDC-PLS), is developed. To obtain all the possible wavelength intervals, our method mainly consists of two steps. First, an effective iterative procedure based on distance correlation is used to screen wavelength interval variables. Then, build a series of PLS models by recursive using all the wavelength intervals but one interval until the optimal wavelength intervals obtain, which correspond the lowest root mean square error of prediction. The IDC-PLS integrates the advantages of distance correlation with PLS method, which is an efficient strategy to enhance the performance of PLS in wavelengths selection. The performance of IDC-PLS was tested on three real NIR datasets. The results demonstrate that IDC-PLS can improve prediction performance and efficiently select strongly correlated wavelength intervals related to the response. The proposed method may be a good wavelength interval selection strategy due to its simplicity and efficiency.
摘要：
In order to solve the problems of high internal stress of core-rim structure, and denitrification behavior of Ti(C, N)-based cermets, nano TiC powders were adopted to promote the diffusion-controlled formation of inner rims and to modify the metal-ceramic interfaces. Based on this, Ti(C,N)-based cermets with 0-8 wt% nano TiC were prepared via solid-state nitrogen-pressure sintering and subsequently Ar-pressure HIP sintering. Nano TiC refined the microstructure and resulted in more white core-rim phase with thicker rims, and ultrafine rimless Ti(C,N). Nano TiC greatly affected the rim-binder interfaces via shifting the equilibrium crystal morphology of (Ti,M) (C, N) in Ni-Co from cubic to octahedron. With the increasing nano TiC content, the orientation relationship of rim binder interface changed from (200)rim//(111)binder to (111)rim//(111)binder, and the interface strain increaseds. Cermets with {200} rim-binder interface exhibited high bending strength but low fracture toughness and tensile strength, owing to the high bonding strength between rim and binder. Otherwise, weakening strength of the rim binder interface could enhance the toughness via the breaking of ceramic-binder boundaries. A promising route for preparing Ti(C,N)-based cermets with satisfactory mechanical properties was put forward, via adjusting the rim-binder interfaces.
关键词：
Bi-based composite;Bi-rich oxyhalide;Internal electric field;Bulk-charge separation
摘要：
Designing semiconductor photocatalyst with high visible-light sensitivity and good photocatalytic performance is still a key issue for pollutant remediation and energy storage. In this work, a series of (BiO)(2)OHCl@Bi24O31Cl10 composite photocatalysts were synthesized through an ammonia-dependent aqueous strategy with (BiO)(2)OHCl as the in-situ formed precursor. More ammonia introduction in the synthetic system led to faster transformation of (BiO)(2)OHCl to Bi24O31Cl10 component and resulted in composites with controllable compositions. The Bi-based heterostructures extended good visible-light absorption ability and strengthened internal electric field (IEF) to induce the generation of charge carriers and promote bulk-charge separation (BCS) efficiency for antibiotic removal. (BiO)(2)OHCl@Bi24O31Cl10 composites with optimum compositions exhibited superior photocatalytic activities on levofloxacin (LEV) degradation under visible-light irradiation, roughly two times higher than that of individual (BiO)(2)OHCl or Bi24O31Cl10 powders. The high degradation efficiency and rapid reaction kinetics would be ascribed to the valid charge transfer from the bulk interior to the surface of composite catalysts. The sheet-like Bi24O31Cl10 at catalyst surface and matched band structures of two components in (BiO)(2)OHCl@Bi24O31Cl10 heterostructures are also proposed as vital factors to influence the photocatalytic performances. This study hopes to provide new insights for the design of visible-light induced bismuth-based photocatalysts for practical applications. (c) 2022 Elsevier B.V. All rights reserved.
作者机构：
[Chen, Xiaohua; Yang, Yujie; Huang, Cong; Zhang, Yan; Hu, Aiping] Hunan Univ, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Coll Mat Sci & Engn, Changsha 410082, Peoples R China.;[Pal, Shubhadeep; Wang, Jiande; Zhang, Yan; Apostol, Petru; Vlad, Alexandru] Catholic Univ Louvain, Inst Condensed Matter & Nanosci, B-1348 Louvain La Neuve, Belgium.;[Liu, Zheng] Hunan City Univ, All Solid State Energy Storage Mat & Devices Key, Coll Mat & Chem Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Prof. Xiaohua Chen] C;College of Materials Science and Engineering, Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology, Hunan University, Changsha, 410082 China
摘要：
In this study, modified sericite is used to improve the bonding performance of polyimide(PI) adhesives which owe to its high temperature resistance, corrosion resistance and low cost. In order to further improve the performance of PI adhesives, PI/sericite composites were prepared by polyamide acid salt method. XRD and SEM analysis show that, after modification, the interlayer spacing of sericite is greatly enlarged, and the lamellar structure of sericite is clearly visible and extremely loose; XRD, TGA and bonding strength found that, The addition of TEA do not change the excellent performance of polyimide, modified sericite lamellae was successfully inserted into the polyimide molecular chain, and the sericite crystal plane spacing expanded and dispersed in the polymer matrix in the form of exfoliation; When the organic sericite content is 3 wt%, the T-5 (2)and T-10 (3)of the modified PI materials are 25 and 21 degrees C higher than that of pure PI, the bonding strength is nearly 20 MPa, which is 29.67% higher than that of pure PI.
作者机构：
[Fang, Fang; Chen, Shanping; Li, Weipeng; Deng, Guo-Jun; Zheng, Haolin] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Green Organ Synth & Applicat Hunan Prov,K, Xiangtan 411105, Peoples R China.;[Fang, Fang] Hunan City Univ, Coll Mat & Chem Engn, Yiyang 413000, Peoples R China.;[Mao, Guojiang] Henan Normal Univ Xinxiang, Sch Chem & Chem Engn, Xinxiang 453007, Peoples R China.
通讯机构：
[Shanping Chen; Guo-Jun Deng] K;Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, 411105 People's Republic of China
摘要：
In this study, a ternary blend modifier (TBM) was prepared with RPE, RPP, and various dosages of PP-g-MAH (i.e., 0%, 1%, 3%, 5%, 7%, and 9% by weight of RPE and RPP) by a twin-screw extruder. The performance of TBM (4% by weight of asphalt) modified asphalt was studied, with the increase of PP-g-MAH content, the penetration decreases gradually, but softening point and viscosity increases and ductility exists minimum value at 7% content, with the increasing of PP-g-MAH percentage, the dynamic rheological properties show that vertical bar G*vertical bar increases, while the d and vertical bar G*vertical bar cos delta decrease, and the fatigue performance (vertical bar G*vertical bar sin delta) of TBM modified asphalt is worse than virgin asphalt. Dynamic stability test shows that TBM shows the prominent high-temperature properties of a modified (asphalt mixture. BBR test indicates that the m-value of asphalt modified with TBM does not fulfill the requirements (m-value> 0.3) except at 5% and 7%, but the S meets the standard requirements (S < 300 MPa), and increases from 0% to 7%, then decreases slightly. In order to illuminate possible reasons, a chemical reaction (ester compounds generated) and physical twines of concerned polymer molecules were put forward, and the results were confirmed by infrared analysis.
期刊：
Journal of Porous Materials,2022年29(1):63-71 ISSN：1380-2224
通讯作者：
Wenxiu cao
作者机构：
[Cao, Wenxiu] Hunan City Univ, Coll Mat & Chem Engn, Hunan Prov Key Lab Dark Tea & Jin Hua, Yiyang, Peoples R China.;[Li, Youji; Zhuo, Ou] Jishou Univ, Key Lab Mineral Cleaner Prod & Exploit Green Func, Jishou 416000, Hunan, Peoples R China.;[Yuan, Bizhen] Jilin Univ, Zhuhai Coll, Coll Chem Engn & New Energy Mat, Zhuhai 519041, Guangdong, Peoples R China.;[Luo, Wenhao] Chinese Acad Sci, Dalian Inst Chem Phys, CAS Key Lab Sci & Technol Appl Catalysis, 457 Zhongshan Rd, Dalian 116023, Peoples R China.
通讯机构：
[Wenxiu cao] H;Hunan Provincial Key Laboratory of Dark Tea and Jin-hua, College of Materials and Chemical Engineering, Hunan City University, Yiyang, People’s Republic of China
摘要：
The structure modification of metal-organic frameworks (MOFs) is a promising technique to enhance its selective adsorption of carbon dioxide at room temperatures. However, to date, little is known on the structure-property relationship of MOFs for carbon capture. In this work, the effects of chemical composition of MOFs on selective adsorption of carbon dioxide were studied systematically. A series of aluminum-based MIL-53 with similar formula units but different organic ligands, Al(OH)BDC-X [BDC = terephthalate, X = H, NH2, NO2, 2(CH3)], were prepared and employed to the selective adsorption of CO2/N-2. It was found that the Al(OH)BDC-X series with various organic ligands affected the CO2 capacity significantly. The decorations of functional groups with strong polarity on the BDC links remarkably enhanced the CO2 uptakes. The experimental results were in good agreement with the equivalent adsorption heat calculations, which showed that the CO2 affinity of the ligands with polarity groups were thermodynamically more favored than those with non-polarity ones on the MOF structures. The interesting findings could provide a potential way to fabricate new metal organic frameworks with high carbon dioxide capture capacities at room temperature.
期刊：
European Food Research and Technology,2021年247(8):1975-1985 ISSN：1438-2377
通讯作者：
Zhang, X.-H.;Qing, X.-D.
作者机构：
[Zhang, Xiao-Hua; Wang, Deguo; Zhang, Ai-Li; Liu, Xue-Jiao; Xiao, Fu-Gang; Guo, Wei-Yun] Xuchang Univ, Henan Key Lab Biomarker Based Rapid Detect Techno, Food & Pharm Coll, Xuchang 461000, Peoples R China.;[Qing, Xiang-Dong] Hunan City Univ, Coll Mat & Chem Engn, Hunan Prov Key Lab Dark Tea & Jin Hua, Yiyang 413049, Peoples R China.;[Liu, Yanhong] ARS, Mol Characterizat Foodborne Pathogens Res Unit, Eastern Reg Res Ctr, USDA, Wyndmoor, PA 19038 USA.
通讯机构：
[Zhang, X.-H.; Qing, X.-D.] H;Henan Key Laboratory of Biomarker Based Rapid-Detection Technology for Food Safety, Food and Pharmacy College, Xuchang University, Xuchang, People’s Republic of China
摘要：
Graphene film is promising candidate as free-standing electrodes for potassium-ion batteries (KIBs) owing to its intrinsic nature of mechanical strength and high electrical conductivity. However, its performance is usually restricted by the tightly stacked structure and sluggish insertion/deinsertion K storage mechanism. Herein, a redox-active engineered holey reduced graphene oxide (HRGO) film anode was prepared by using the carboxylic acid functionalized polystyrene (PS-COOH) spheres as the template. The holey ion diffusion network channels and the oxygen functional groups can be optimized during the PS-COOH spheres decomposition process, which largely promote the enhancement of electrochemical performance because the oxygen functional groups can serve as the surface-redox sites increasing surface-driven reactions and holey channels provide more ion-accessible area for K-ion storage. Moreover, the reduction degree of graphene oxide also be simply tuned by changing the annealing temperature, which can improve the K+ bulk intercalation reaction. As a result, the optimized HRGO-900 (HRGO sample obtained at 900 degrees C) films exhibits a superior areal capacity (0.80 mAh cm(-2) at 0.1 mA cm(-2)). The electrode design and construction strategies can be effectively applied in other 2D materials, which exhibits practical applications in energy storage devices. (C) 2020 Elsevier Ltd. All rights reserved.
期刊：
International Journal of Applied Ceramic Technology,2021年18(3):781-791 ISSN：1546-542X
通讯作者：
Xiong, Huiwen;Gan, Xueping
作者机构：
[Gan, Xueping; Xie, Dan; Zhou, Kechao; Li, Zhiyou; Xiong, Huiwen; Wu, Yuxue; Gan, XP] Cent South Univ, State Key Lab Powder Met, Changsha 410083, Peoples R China.;[Xie, Dan] Hunan City Univ, Coll Mat & Chem Engn, All Solid State Energy Storage Mat & Devices Key, Yiyang, Peoples R China.
通讯机构：
[Xiong, HW; Gan, XP] C;Cent South Univ, State Key Lab Powder Met, Changsha 410083, Peoples R China.
关键词：
Core-shell structures;Electroless plating;Microstructure;Ni-coated TiN composite powders;TiN-Ni cermets
摘要：
To solve the poor sinterability and wettability between TiN ceramic and pure metal via using coated composite powders, dense TiN-Ni cermets with uniform microstructure and fine grains were developed at a low sintering temperature of 1300celcius in this work. TiN powders were firstly activated in a strong acid solution, in order to achieve a step-like surface; Ni-coated TiN powders showed an uniform and controllable morphology. Two types of TiN-Ni cermets based on conventional milled powders and Ni-coated TiN composite powders were fabricated by spark plasma sintering (SPS), and used for the comparison concerning the sintering behavior, microstructure and related mechanical properties. Results showed that Ni-coated TiN composite powders helped to improve the sinterability between ceramic and metal, which is rather beneficial to obtain dense TiN-Ni cermets with homogeneous microstructure and high mechanical properties. Compared to those of conventional TiN-Ni, the relative density, Rockwell hardness and fracture toughness increased from 84.9% to 96.6%, 80.2 to 84.3, and 10.2 MPa center dot m(1/2) to 14.7 MPa center dot m(1/2), with a rather low sintering temperature of 1300 celcius, respectively.
摘要：
The synthesis of sulfur heterocycles via the construction of C–S bonds has received considerable attention due to their biological value and extensive pharmaceutical application. While diverse sulfurating agents have been developed over the past few decades, in this regard, elemental sulfur, with advantages of low toxicity, odorless nature and chemical stability, has great potential for the construction of diverse sulfur heterocycles through its direct incorporation into the target molecules in a concise way. Direct functionalization of inert C–H bonds can shorten the number of reaction steps and minimize the amount of waste formed. Hence, heteroannulations via direct C–H sulfuration is considered to be an attractive strategy for the synthesis of sulfur heterocycles. In the last few years, a vast array of concise systems have been reported for the synthesis of some valuable sulfur heterocycles such as thiophenes, thienoindoles, thienothiazoles, thiazoles, benzothiazoles, and thiadiazoles through direct C–H sulfuration/annulations with elemental sulfur. These are discussed in detail in this review.
1 Introduction
2 Thiophenes
3 Thienoindoles
4 Thienothiazoles
5 Other Fused Thiophenes
6 Thiazoles
7 Benzothiazoles
8 Thiadiazoles
9 Others
10 Summary and Outlook
摘要：
For the first time, alternating trilinear decomposition-assisted multivariate curve resolution (ATLD-MCR) was applied to analyse complex gas chromatography-mass spectrometric (GC-MS) data with severe baseline drifts, serious co-elution peaks and slight retention time shifts for the simultaneous identification and quantification of polycyclic aromatic hydrocarbons (PAHs) in aerosols. It was also compared with the classic multivariate curve resolution-alternating least-squares (MCR-ALS) and the GC-MS-based external standard method. In validation samples, average recoveries of five PAHs were within the range from (96.2 +/- 6.8)% to (106.5 +/- 4.1)% for ATLD-MCR, near to the results of MCR-ALS ((98.0 +/- 1.5)% to (106.7 +/- 4.3)%). In aerosol samples, the concentrations of pyrene provided by ATLD-MCR were not significantly different from those of MCR-ALS. The other four PAHs including chrysene, benzo[a]anthracene, fluoranthene and benzo[b]fluoranthene were not detected by ATLD-MCR and the GC-MS-based external standard method. The results of figures of merit further demonstrated that ATLD-MCR achieved high sensitivities (8.9 x 10(4) to 1.7 x 10(6) mAU ml mu g(-1)) and low limits of detection (0.003 to 0.087 mu g ml(-1)), which were better than or similar to MCR-ALS, presenting a great choice to deal with complex GC-MS data for the simultaneous determination of targeted PAHs in aerosols.
