Micromachines
·
2021
·Vol. 12
·期 2
·121
·
IF 2.891
Yue Su,Zhaoxin Geng,Weihao Fang,Xiaoqing Lv,Shicai Wang,Zhengtai Ma,Weihua Pei
Nanoimprint technology is powerful for fabricating nanostructures in a large area. However, expensive equipment, high cost, and complex process conditions hinder the application of nano-imprinting technology. Therefore, double-layer self-priming nanoimprint technology was proposed to fabricate ordered metal nanostructures uniformly on 4-inch soft and hard substrates without the aid of expensive instruments. Different nanostructure (gratings, nanoholes and nanoparticles) and different materials (metal and MoS2) were patterned, which shows wide application of double-layer self-priming nanoimprint technology. Moreover, by a double-layer system, the width and the height of metal can be adjusted through the photoresist thickness and developing condition, which provide a programmable way to fabricate different nanostructures using a single mold. The double-layer self-priming nanoimprint method can be applied in poor condition without equipment and be programmable in nanostructure parameters using a single mold, which reduces the cost of instruments and molds.Keywords:double-layer;nanoimprint;wafer-scale;nanostructure
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2014
·
IF 2.726
Wenlong Yin,Kai Feng,Lei Kang,Bin Kang,Jianguo Deng,Zheshuai Lin,Jiyong Yao,Yicheng Wu
The first two members in the quaternary A/A′/M/Q (A = alkali metal; A′ = alkaline-earth metal; M = As, Sb, Bi; Q = S, Se, Te) system, namely the KBaMSe 3 (M = As, Sb) selenides, have been synthesized by solid state reactions. They are isostructural and crystallize in the centrosymmetric space group P 2 1 / c of the monoclinic system. In the structure, the trivalent M atom (M = As, Sb) is coordinated to three Se atoms forming a trigonal pyramid with the Se atoms serving as the triangle base, showing the stereochemical activity of the ns 2 lone pair electron. The MSe 3 (M = As, Sb) trigonal pyramids are totally isolated from each other with K + and Ba 2+ cations located between them. The optical band gaps of 2.26 (2) eV for KBaAsSe 3 and 2.04 (2) eV for KBaSbSe 3 , were deduced from the diffuse reflectance spectra. The first principles calculations were performed to study the electronic structures of KBaMSe 3 (M = As, Sb) compounds and the results indicated that these two compounds are indirect band gap semiconductors.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2014
·
IF 2.016
Xin Wang,Kuo Jiang,Liang Zhou
Powders of (Nd 1− x Ce x ) 2 Zr 2 O 7+ y ( x = 0–1) with pyrochlore structure were prepared by sol-spray pyrolysis and subsequent graphite reduction at 1200 °C. The effects of cerium content on crystal structure, phase stability and microstructure of the (Nd 1− x Ce x ) 2 Zr 2 O 7+ y ( x = 0–1) inert matrix materials were studied. XRD and Raman results presented that all samples were in a single pyrochlore phase. XPS results indicated the cerium was in a single oxidation state of +4. After sintering at 1500 °C for 24 h in air, the sample of x = 1 underwent a phase segregation to Zr 1− x Ce x O 2 solid solutions of tetragonal, metastable tetragonal and cubic phases, the sample of x = 0.9 contained a few tetragonal phase in addition to fluorite phase, the samples of x = 0.5–0.8 had a single phase fluorite structure, the samples of x = 0–0.4 maintained the pyrochlore structure.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2021
·
IF 4.889
Peng Wu,Yuan Xiong,Chen Lei,Yuan Li,Xiang Liu,Cheng Zhang,Yudie Sun,Jian Zhang,Chun-Sing Lee,Kui Zhang
Carbon dots or Carbon quantum dots (herein after abbreviated as CDs) with bight luminescence, derived from carbohydrates such as citric acid , glucose or sucrose, have been widely reported in recent publications. However, as to which functional groups and structures in CDs are responsible for luminescence, most explanations in current references are normally based on assumptions, instead of being convinced by the accurate information resting on experimental facts. Herein, we conducted an experimental study targeting at finding the fluorophores of CDs prepared from citric acid and glycine by fluorescent quenching. The experimental results revealed that the essence of fluorescence was manipulated by fluorophores of conjugated C C double bonds and aldehyde groups. The destruction of aldehyde groups or C C double bonds in the CDs led to a complete decay of luminescence. In addition, the results of this experiment were similar to those of CDs prepared from the sole citric acid, glucose or sucrose, which predicted the analogy of the CDs in chemical structures . Such information about fluorophore of CDs was valuable for further exploring more extensive application of CDs in sense technologies.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Haijian Qin,Zelong Yang,Qing Xia,PeifeiYao,Chunzhi Zheng,Guangpin Lin,Zhaolian Ye,Songjian Zhao,Fengli Yang
Because the combination of Co and common support (Al, Ti, et al.) usually shows poor catalytic activity, tantalum has been introduced for CO conversion as a novel carrier due to the excellent performance. In this work, Co 3 O 4 was loaded on four forms of tantalum support (amorphous, mesoporous, crystalline and crystalline mesoporous, abbreviated as Co/Ta-am, Co/Ta-me, Co/Ta-cry and Co/Ta-cm, respectively). And among these four states, Co/Ta-cm presents the highest CO conversion rate. The temperature of 90% CO conversion rate of Co/Ta-cm is approximately 130 ℃ at the high space velocity of 780,000 h −1 , which is 70%, 82% and 88% higher than that of Co/Ta-cry, Co/Ta-me and Co/Ta-am, respectively. Moreover, the characteristics of the catalyst have been studied by XRD, SEM, BET, TGA, and H 2 -TPR, and the results reveal that Co/Ta-cm has the excellent crystallinity and stability, and the morphology is regular. X-ray photon spectroscopy and in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) have been performed to investigate the reaction mechanism, which indicates that Co 3+ is the active component and lattice oxygen plays a critical role in CO oxidation.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Innovative Food Science & Emerging Technologies
·
2024
·
IF 6.3
Debao Niu,Yuanxin Feng,Xin-An Zeng,Jun-Hu Cheng
Pulsed electric fields (PEF) can affect enzyme activity in fruit and vegetable juice, but its effect on microbial cellular enzymes has not been fully revealed. Alcohol dehydrogenase (ADH) is a key cellular enzyme of Acetobacter sp. to convert alcohol to acetic acid by metabolism. In this study, the effect of PEF treatment on the ADH activity of Acetobacter sp. and the structural changes of the enzyme were systematically investigated. The results showed that the activity of cellular ADH in Acetobacter sp. was decreased by PEF treatment. The α -helix structure of ADH molecules decreased and the random coil structure increased, indicating a change in secondary structure. The tertiary structure of ADH was expanded and the microenvironment of aromatic amino acid residues was changed, while the primary structure of molecules remained intact. In conclusion, the decrease of ADH activity after PEF treatment may be caused by the transformation of spatial conformation.
研究领域:
微生物学
·
生物化学
·
食品科学
·
酶学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2020
·
IF 4.469
Yanting Wang,Hao-Kai Peng,Ting-Ting Li,Bing-Chiuan Shiu,Xuefei Zhang,Ching-Wen Lou,Jia-Horng Lin
Electromagnetic pollution often interferes with nearby electronic equipment and poses a serious threat to the health of people. There is an urgent need to develop soft and lightweight electromagnetic interference (EMI) shielding materials. In this study, a layer-by-layer self-assembly strategy was used implemented to prepare PAN@Ag@PDA@PPy (PAP@PPy) films with unique core-shell and sandwich composite microstructures for electromagnetic interference (EMI) shielding. Results showed that the conductivity of the composite films was the highest at 898.72 S/m after in situ polymerization of pyrrole at low temperatures. The mechanical properties of the conductive films also increased from the initial 16.81 MPa to 22.54 MPa. The average shielding effectiveness (SE) and SSE/t of the composite films with two layers reached as high as 23.81 dB and 6764.20 dB cm 2 g −1 , respectively. This performance was caused originates from by the layer structure of the PAN film and multiple internal reflections from the interconnected core-shells and sandwich microstructures in of the PAP@PPy films. Therefore, this work study gave provides a new novel strategy for fabricating conductive polymer composites (CPCs) with high-performance EMI shielding.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Xiaodong Dong,Jinsheng Sun,Xianbin Huang,Kaihe Lv,Yuan Geng,Fengbao Liu,Zonglun Wang,Xianfa Zhang
ABSTRACT In the process of developing deep oil and gas resources, the problem of high temperature and high salinity in deep strata has become a serious challenge faced by water-based drilling fluids. Under high temperature and high salinity conditions, drilling fluids must maintain good rheological properties to ensure safe and efficient drilling work. In this study, a temperature- and salt-resistant viscosifier (DASL) was synthesized using N, N-dimethylacrylamide, 2-Acrylamido-2-methylpropane sulfonic acid, sodium p-styrene sulfonate, and lauryl methacrylate as monomers with a double backbone structure of micro crosslinking and hydrophobic association structures. The results of pyrene fluorescence probe test and transmission electron microscopy observation showed that DASL has an obvious hydrophobic associative structure. Moreover, due to the presence of microcrosslinked structure, DASL exhibits good shear thinning property and thixotropy in aqueous solution. Under the conditions of 200℃ and 35 wt% NaCl, the apparent viscosity of the drilling fluid with 2 wt% DASL added was 24.5 mPa⸱s, and the filtration was only 9.2 mL. In addition, mechanism studies have shown that the dual skeleton structure of DASL improves its temperature and salt resistance. DASL can adsorb and bridge with bentonite particles, increase the internal friction and structural viscosity of the drilling fluid, enhance the internal mesh structure of the drilling fluid, improve the colloidal stability of the drilling fluid, and maintain a reasonable particle size distribution of the bentonite particles, which enable DASL to significantly increase the viscosity of the drilling fluid while reducing the filtration loss of the drilling fluid. This work demonstrates that polymers with dual skeleton structures of micro crosslinking and hydrophobic association have good application effects as temperature- and salt-resistant viscosifier for water-based drilling fluids.
研究领域:
石油工程
·
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 2
·292
·
IF 4.034
Zhi Zhang,Xuliang Lv,Yiwang Chen,Pin Zhang,Mingxu Sui,Hui Liu,Xiaodong Sun
For the purposes of strength, military equipment camouflage, and protecting the health of organisms, electromagnetic wave absorbing materials have received a lot of attention and are widely studied. In addition to having a strong absorption intensity and a wide effective absorption bandwidth, materials that are lightweight, thermally stable, and antioxidative are also highly desirable. In this study, we fabricated core–shell structured NiS2@MoS2nanospheres anchored on reduced graphene oxide (rGO) nanosheets (NiS2@MoS2/rGO) by a simple two-step hydrothermal method. The combination ratio was adjusted to achieve proper impedance matching. The electromagnetic parameters and the absorption performance were investigated in detail. A composite loaded with 30 wt.% of the sample achieved a minimum reflection loss (RL) value of −29.75 dB and the effective bandwidth (RL value of less than −10 dB) ranged from 4.95 GHz to 18.00 GHz (13.05 GHz), with a thickness ranging from 1.5 mm to 4.0 mm. This study proved that the generated significant interfacial polarization and synergetic interaction between components can result in NiS2@MoS2/rGO composites with enhanced electromagnetic absorption performance.Keywords:graphene;core–shell;heterostructure;electromagnetic absorption
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 40
·16530-16540
·
IF 3.5
Xuekai Wang,Yongze Cao,Xianglan Yan,Sai Xu,Jinsu Zhang,Tianshuo Liu,Baojiu Chen
Cubic and hexagonal structured SrTa4O11(STO):Er3+/Yb3+ phosphors were synthesized by a solid state reaction (SSR) and molten salt synthesis (MSS). The upconversion luminescence (UCL) intensity of these samples was investigated. Hexagonal STO:Er3+/Yb3+ with much or a little β-Ta2O5 can be synthesized by SSR in air or vacuum, respectively, and the UCL intensity of the sample synthesized by SSR in a vacuum is higher. Cubic STO:Er3+/Yb3+ can be synthesized by MSS with KCl flux, and hexagonal STO:Er3+/Yb3+ can be synthesized by MSS with B2O3 flux, which has the strongest UCL intensity among all the samples compared with samples prepared by SSR. The sample by MSS with B2O3 flux was acid pickled (AP) with HCl solution, and the green UCL intensity increased by 2.18 times, which reached 32.95% for β-NaYF4:Er3+/Yb3+. The UCL intensity of the hexagonal STO:Er3+/Yb3+ is much higher than that of the cubic structure, which is due to the layered structure and the non-central symmetry of the Er3+/Yb3+ doped sites in hexagonal STO:Er3+/Yb3+. The temperature sensitivity of samples is evaluated by luminescence intensity ratio (LIR) technology. The maximum relative sensitivity is 0.0099 K−1 at 303 K. All the results show that hexagonal STO:Er3+/Yb3+ has excellent pure green UCL intensity and high temperature sensitivity, which can be used in UCL display and temperature sensing.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Animals
·
2025
·Vol. 15
·期 6
·865
·
IF 2.7
Chengcheng Wu,Lihan Tao,Quanyong Zhou,Fanfan Zhang,Yanbing Zeng
Simple SummaryThe helicase NSP13, encoded by porcine deltacoronavirus (PDCoV), regulates viral replication and is considered to bean ideal target for antiviral drugs. In our work, the wild-type NSP13WTand various deletion mutants were generated through expression and purification, and we tested the activities of these proteins using multiple methods. The results revealed that both the Stalk and 1B domains were necessary for NSP13WTto separate the double-stranded nucleic acids, and the deletion of the ZBD impaired this unwinding activity. Our study is the first to explore the role of each domain in the activities of PDCoV NSP13, providing mechanistic insights into helicase-regulated viral replication and laying the foundation for the development of antiviral drugs.The nonstructural protein 13 (NSP13) of PDCoV is a highly conservative helicase and plays key roles in viral replication. NSP13 contains a zinc-binding domain (ZBD), a helical Stalk domain, a beta-barrel 1B domain, and a core helicase domain. However, the specific functions of these domains of PDCoV NSP13 remain largely unknown. Here, we expressed and purified the wild-type NSP13WTand various mutants with domain deletions, and the activities of these proteins were analyzed using multiple methods. We found that NSP13ΔZBDpossessed the abilities to hydrolyze ATP and unwind double-stranded nucleic acids, but the unwinding efficiency was lower than that of NSP13WT. In contrast, NSP13ΔZBD-Stalk, NSP13Δ1B, and NSP13ΔZBD-Stalk-1Ball lost their unwinding activity, but not their ATPase activity. These results revealed that the deletion of the ZBD impaired the unwinding activity of PDCoV helicase NSP13, and the Stalk and 1B domains were critical for NSP13 to separate the duplexes. The identification of the roles of each domain in this study was helpful to gain an in-depth understanding of the overall functions of helicase NSP13, providing a theoretical basis for the development of antiviral drugs targeting helicase.
研究领域:
病毒学
·
分子生物学
·
抗病毒药物开发
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Yanmeng Cai,Yue Wang,Le Zhang,Rongli Fang,Jixiao Wang
Two-dimensional (2D) layered transition-metal carbides (MXenes) are attractive faradic materials for an efficient capacitive deionization (CDI) process owing to their high capacitance, excellent conductivity, and remarkable ion storage capacity. However, the easy restacking property and spontaneous oxidation in solution by the dissolved oxygen of MXenes greatly restrict their further application in the CDI domain. Herein, a three-dimensional (3D) heterostructure (MoS2@MXene) is rationally designed and constructed, integrating the collective advantages of MXene flakes and MoS2 nanosheets through the hydrothermal method. In such a design, the well-dispersed MXene flakes can effectively reduce the aggregation of MoS2 nanosheets, boost electrical conductivity, and provide efficient charge transfer paths. Furthermore, MoS2 nanosheets as the high-capacity interlayer spacer can prevent the self-restacking of MXene flakes and provide more active sites for ion intercalation. Meanwhile, the strong chemical interactions between MXene flakes and MoS2 nanosheets contribute to accelerating the charge transfer kinetics and enhancing structural stability. Consequently, the resulting MoS2@MXene heterostructure electrode possesses high specific capacitance (171.4 F g–1), fast charge transfer and permeation rate, abundant Na+ diffusion channels, and superior electrochemical stability. Moreover, the hybrid CDI cell (AC//MoS2@MXene) with AC as the anode and MoS2@MXene as the cathode delivers outstanding desalination capacity (35.6 mg g–1), rapid desalination rate (2.6 mg g–1 min–1), excellent charge efficiency (90.2%), and good cyclic stability (96% retention rate). Most importantly, the MoS2@MXene electrode can keep good structural integrity after the long-term repeated desalination process due to the effective shielding effect of the MoS2 layer to protect MXenes from being further oxidized. This work presents the flexible structural engineering to realize excellent ion transfer and storage process by constructing the 3D heterostructure.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）