作者机构:
[Zhao, Yuelong; Zhang, Peng; Fan, Yali] Taiyuan Univ Technol, Coll Environm Sci & Engn, Taiyuan 411201, Peoples R China.;[Zhang, Peng] Shanxi Normal Univ, Upgrading Off Modern Coll Humanities & Sci, Linfen 041000, Peoples R China.;[Zhang, Peng; Zhang, Wei] Hunan Univ Sci & Technol, Coll Civil Engn, Xiangtan 411201, Peoples R China.;[Zhang, Wei] Changsha Univ Sci & Technol, Coll Hydraul Engn, Changsha 410114, Peoples R China.
通讯机构:
[Wei Zhang; Peng Zhang] C;College of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, China<&wdkj&>College of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China<&wdkj&>College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 411201, China<&wdkj&>Upgrading Office of Modern College of Humanities and Sciences of Shanxi Normal University, Linfen 041000, China<&wdkj&>College of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
摘要:
Abstract: In this study, CTS-GSH was prepared by grafting thiol (–SH) groups onto chitosan (CTS), which was characterized through Fourier Transform Infrared (FT-IR) spectra, Scanning Electron Microscopy (SEM) and Differential Thermal Analysis–Thermogravimetric Analysis (DTA-TG). The performance of CTS-GSH was evaluated by measuring Cr(VI) removal efficiency. The –SH group was successfully grafted onto CTS, forming a chemical composite, CTS-GSH, with a rough, porous and spatial network surface. All of the molecules tested in this study were efficient at removing Cr(VI) from the solution. The more CTS-GSH added, the more Cr(VI) removed. When a suitable dosage of CTS-GSH was added, Cr(VI) was almost completely removed. The acidic environment at pH 5–6 was beneficial for the removal of Cr(VI), and at pH 6, the maximum removal efficiency was achieved. Further experimentation showed that with 100.0 mg/L CTS-GSH for the disposal of 5.0 mg/L Cr(VI) solution, the removal rate of Cr(VI) reached 99.3% with a slow stirring time of 8.0 min and sedimentation time of 3 h; the presence of four common ions, including Mg2+, Ca2+, SO42− and CO32−, had an inhibitory effect on CTS-GSH’s ability to remove Cr(VI) from the aqueous solution, and more CTS-GSH was needed to reduce this inhibiting action. Overall, CTS-GSH exhibited good results in Cr(VI) removal, and thus has good potential for the further treatment of heavy metal wastewater. Keywords: hexavalent chromium; chitosan; reduced glutathione; chelating agent; amidation reaction; flocculation
通讯机构:
[Yonggang Tong] C;College of Automobile and Mechanical Engineering, Changsha University of Science and Technology, Changsha, People’s Republic of China
摘要:
Developing advanced materials with excellent mechanical properties and high-temperature oxidation performance are important to the potential application in high-temperature structural parts. In the paper, CoCrNiAlxY (x = 0.2, 0.6, 1.0 and 1.4) middle entropy alloys were prepared, and the effects of Al content on the microstructure, mechanical properties and oxidation behavior at 1200 degrees C of CoCrNiAlxY middle entropy alloys were studied. The phase of CoCrNiAlxY alloys is changing from FCC to BCC with increasing Al content; thereinto, CoCrNiAl0.6Y alloy forms duplex FCC plus BCC phase structure. The hardness and fracture strength of CoCrNiAlxY (x = 0.2, 0.6, 1.0) alloys increase with increasing Al content. When Al content is 1.4, the hardness and fracture strength of CoCrNiAl1.4Y alloy decrease, which result from the tiny variation of alloy microstructure. The oxidation behavior at 1200 degrees C of CoCrNiAlxY alloys confirms that compact aluminum oxide film can be formed on the CoCrNiAl0.6Y alloy, which slows down the oxidation rate of the alloy. The CoCrNiAl0.6Y alloy has the best oxidation resistance with lower oxidation rate of 1.467 x 10(-11) g(2)/(cm(4) s).
摘要:
The development of multifunctional composites is a challenging but necessary path for the miniaturization and integration of electronic products. Herein, versatile bimetal hydroxide (NiCo2(OH)(6)) nanowires coated on TiO2 modified lignin based carbon nanofibers (CNFs/TiO2@NiCo2(OH)(6)) have been prepared successfully by the method of electrospinning followed by hydrothermal treatment. The loading of NiCo2(OH)(6), the doping of N, and the modification of TiO2 endow the CNFs/TiO2@NiCo2(OH)(6) with multifunctional application in energy storage and microwave absorption (MA). The abundant pores and active sites result in an excellent electrochemical performance with a high specific capacitance of 752.47 F g(-1) at 1 A g(-1). More importantly, the assembled supercapacitor exhibits a maximum energy density of 60.64 Wh kg(-1) and a superior stability of 90.2 % even after 4000 cycles at the current density of 10 A g(-1). Moreover, considering the unique porous layered-structure as well as eminent electromagnetic matching properties, as-prepared composites display an excellent MA property, which possesses a minimum reflection loss (RLmin) of -46.48 dB and a maximum effective absorption bandwidth (EAB, RL < 10 dB) of 2 GHz (covering 47.62 % of X-band frequency). This work simultaneously delivers the potential application in the field of energy storage and MA.
作者机构:
[Li, Junbin; Ma, Xiaofei; Qing, Zhihe; Zhang, Yue-Fei; Zhou, Yibo; Hu, Shan] Changsha Univ Sci & Technol, Sch Chem & Chem Engn, Hunan Prov Key Lab Cytochem, Hunan Prov Key Lab Mat Protect Elect Power & Trans, Changsha 410114, Peoples R China.;[Yang, Sheng; Yang, Ronghua] Hunan Normal Univ, Coll Chem & Chem Engn, Lab Chem Biol & Tradit Chinese Med Res, Minist Educ, Changsha 410081, Peoples R China.;[Guo, Jingru] China Pharmaceut Univ, Dept Pharmaceut Anal, State Key Lab Nat Med, Key Lab Drug Qual Control & Pharmacovigilance, Nanjing 210009, Peoples R China.;[Liu, Juewen] Univ Waterloo, Waterloo Inst Nanotechnol, Dept Chem, Waterloo, ON N2L 3G1, Canada.
通讯机构:
[Qing, ZH ] C;[Yang, RH ] H;Changsha Univ Sci & Technol, Sch Chem & Chem Engn, Hunan Prov Key Lab Cytochem, Hunan Prov Key Lab Mat Protect Elect Power & Trans, Changsha 410114, Peoples R China.;Hunan Normal Univ, Coll Chem & Chem Engn, Lab Chem Biol & Tradit Chinese Med Res, Minist Educ, Changsha 410081, Peoples R China.
摘要:
ATP,a small molecule with high intracellular concentration (mMlevel), provides a fuel to power signal amplification, which is meaningfulfor biosensing. However, traditional ATP-powered amplification isbased on ATP/aptamer recognition, which is susceptible to the complexbiological microenvironment (e.g., nuclease). In this work, we communicatea signaling manner termed as ATP-specific polyvalent hydrogen binding(APHB), which is mimetic to ATP/aptamer binding but can avoid interferencefrom biomolecules. The key in APHB is a functional fluorophore thatcan selectively bind with ATP via polyvalent hydrogen, and the fluorescencewas lighted with the changes of the molecular structure from flexibilityto rigidity. By designing, synthesizing, and screening a series ofcompounds, we successfully obtained an ATP-specific binding-lightedfluorophore (ABF). Experimental verification and a complex analoguedemonstrated that two melamine brackets in the ABF dominate the polyvalenthydrogen binding between the ABF and ATP. Then, to achieve amplificationbiosensing, fibroblast activation protein (FAP) in activated hepaticstellate cells was taken as a model target, and a nanobeacon consistingof an ABF, a quencher, and an FAP-activated polymer shell was constructed.Benefiting from the ATP-powered amplification, the FAP was sensitivelydetected and imaged, and the potential relationship between differentiationof hepatocytes and FAP concentration was first revealed, highlightingthe great potential of APHB-mediated signaling for intracellular sensing.
摘要:
LaPO4-8YSZ composite coatings with a thickness of similar to 1 mm have been developed for increasing thermal protection of combustion chamber components in gas turbines and diesel engines. A serious problem concerning the thick coatings is the high residual stress, which results in poor adhesion and low thermal shock resistance. In this study, thick LaPO4-8YSZ composite coatings in different compositions were produced by atmospheric plasma spraying at four different critical plasma spraying parameters (CPSP; 0.83, 0.94, 1.06 and 1.17 kW/Lpm). The effects of CPSP on microstructure, residual stress and mechanical properties of LaPO4-8YSZ thick composite coatings were investigated. The results shows that the porosity of the coatings is decreased with the increase of CPSP from 0.83 to 1.17. The decreasing porosity leads to the increase of Young's modulus and microhardness of the coatings, while the fracture toughness of the coatings shows a decreasing tendency. The residual stress in the composite coatings increases with increasing CPSP. Correspondingly, the thermal shock resistance of the coatings decreases with the increase of CPSP. The 5 wt% LaPO4-8YSZ composite coating has the lowest residual stress at CPSP 0.83 and it exhibits the longest thermal cycle life at 1000 degrees C (1355 +/- 134 cycles).
摘要:
L-Lysine (L-Lys) quantification in serum using a novel and highly selective amperometric biosensor has been reported. In this study, an efficient, enzyme-free, and simple anti-fouling biosensor was developed based on a self-screened peptide aptamer. A glassy carbon electrode (GCE) was used to construct anti-fouling interfaces by modifying its surface with polyaniline (PANI) polymer. The peptide aptamer, Cys-Pro-Pro-Pro-Pro-Arg-Glu-AsnIle-Gln-Arg-Leu-Thr, was then immobilized onto this electrode via an electroactive cysteine linker and its potential in the determination of L-Lys was examined. Under optimised experimental conditions, the peptide modified electrodes exhibited excellent anti-fouling and electrochemical sensing. The biosensor was effective in resisting biofouling in a wide range of serum samples and amino acid solutions, and its linear range for L-Lys detection ranged from 1 nM to 10 mM, with a comparatively lower detection limit (0.3 nM; S/N = 3). The antifouling biosensor could detect L-Lys in real serum samples, and this approach of designing peptide aptamers based low-fouling biosensors can easily be extended to the development of a bio-sensing platform system for a variety of other metabolites.
摘要:
LiNi(0.8)Co(0.1)Mn(0.1)O(2)(NCM811) is one of the most promising cathode materials for high-energy lithium-ion batteries, but there are still problems such as rapid capacity decay during charge and discharge and poor cycle performance. Elemental doping can significantly improve the electrochemical performance of high nickel ternary cathode materials. In this work, Nb(5+)-doped NCM811 cathode material was successfully synthesized. The results show that Nb(5+)doping helps to increase the interlayer spacing of the lithium layer, electron transport, and structural stability, thereby significantly improving the conductivity of Li(+). At a high voltage of 4.6 V, the initial discharge specific capacity of 1% Nb(5+)-doped NCM811 cathode material at 0.1 C is 222.3 mAh·g(-1), and the capacity retention rate after 100 cycles at 1 C is 92.03%, which is far more than the capacity retention rate of NCM811 under the same conditions (74.30%). First-principles calculations prove that 1% Nb(5+)-doped NCM811 cathode material shows the highest electronic conductivity and Nb(5+)doping will not change the lattice structure, demonstrating the effectiveness of the proposed strategy.
通讯机构:
[Gong, FC ] C;Changsha Univ Sci & Technol, Coll Chem & Chem Engn, Changsha 410114, Peoples R China.
摘要:
A "two-step" preparation method of an excited-state intermolecular proton transfer (ESIPT) fluorescent polymer (f-PP) is reported here. The synthesis of f-PP involves the acetylation of polystyrene and a "multicomponent one pot" reaction. The as-prepared polymer bears a group of ESIPT fluorescent units, enabling it to exhibit high brightness, moderate solubility and ESIPT fluorescence. F-PP gives off tautomeric bright green fluorescence under UV-tamp and the dual-emission could be specifically suppressed by Cr(vi). This phenomenon cannot be elicited by other competing species. On this basis, an ESIPT polymeric probe-based method for the determination of Cr(vi) was developed, offering high sensitivity (19.5 nM) and selectivity. The f-PP was successfully used to detect Cr(vi) in real water samples by standard adding methods, indicating its application feasibility.