Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum...Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum-assisted filtration.Interestingly,within the polytetrafluoroethylene(PTFE)-carbon nanotube(CNT)-Fe_(3)O_(4)layer(FCFe),CNT nanofibers interweave with PTFE fibers to form a stable“silk-like”structure that effectively captures Fe_(3)O_(4)particles.By incorporating a highly conductive MXene layer,the FCFe/MXene(FCFe/M)membrane exhibits excellent electrical/thermal conductivity,mechanical properties,and flame retardancy.Impressively,benefiting from the rational regulation of component proportions and the design of a Janus structure,the FCFe/M membrane with a thickness of only 84.9μm delivers outstanding EMI shielding effectiveness of 44.56 dB in the X-band,with a normalized specific SE reaching 10,421.3 dB cm^(2)g^(-1),which is attributed to the“absorption-reflection-reabsorption”mechanism.Furthermore,the membrane demonstrates low-voltage-driven Joule heating and fast-response photothermal performance.Under the stimulation of a 3 V voltage and an optical power density of 320 mW cm^(-2),the surface temperatures of the FCFe/M membranes can reach up to 140.4 and 145.7℃,respectively.In brief,the FCFe/M membrane with anti-electromagnetic radiation and temperature regulation is an attractive candidate for the next generation of wearable electronics,EMI compatibility,visual heating,thermotherapy,and military and aerospace applications.展开更多
Electromagnetic wave(EMW)absorbers with anti-corrosion property are highly desired to enhance the durability of military targets in harsh condition.Herein,cross-link NiAl-layered double hydroxide(NiAl-LDH)nanosheets o...Electromagnetic wave(EMW)absorbers with anti-corrosion property are highly desired to enhance the durability of military targets in harsh condition.Herein,cross-link NiAl-layered double hydroxide(NiAl-LDH)nanosheets on the inner/outer surfaces of carbon microtubes(CMTs)are ingeniously constructed through the combination of atomic layer deposition technique and a hydrothermal method.The obtained NiAl-LDH/CMT composite exhibits excellent EMW absorption and corrosion resistance performance.The large internal cavity of CMT significantly enhances impedance matching.The uniform distribution of NiAl-LDH nanosheets on both the inner and outer surfaces of CMT generates numerous heterogeneous inter-faces that induce substantial polarization loss.Consequently,at a filler rate of only 5 wt.%,the NiAl-LDH/CMT composite exhibits a minimum reflection loss of−60.2 dB and a maximum effective absorp-tion bandwidth of 5.9 GHz.In addition,the combined high impermeability of CMT and the effective Cl^(-)-trapping ability of NiAl-LDH endows NiAl-LDH/CMT composite with outstanding corrosion protection property in simulated seawater environment.Furthermore,the PO_(4)^(3-)anions are effectively incorporated into the NiAl-LDH interlayer via anion exchange,which can further enhance corrosion protection capac-ity through surface inactivation from slow-release PO_(4)^(3-)anions without reducing their EMW absorption performance.In summary,this work can give guidance for the development of efficient anti-corrosion EMW absorption materials.展开更多
Heterogeneous catalysis on solid surfaces provides high-value chemicals and is involved in a large fraction of the world’s economic productivity,yet our understanding of this important class of processes remains limi...Heterogeneous catalysis on solid surfaces provides high-value chemicals and is involved in a large fraction of the world’s economic productivity,yet our understanding of this important class of processes remains limited.Thermal reaction rates obtained from experiments on mod-el catalysts provide quantitative data that can reveal reaction mechanisms and provide benchmarks for computational simulations of catalytic processes.This perspective describes a critical advance in measuring these rates:velocity resolved kinetics(VRK).VRK delivers ab-solute rates for elementary surface reactions that are of sufficient accuracy that they may be meaningfully compared to theoretical rate predictions,creating a powerful synergy between theory and experiment.It is now routinely possible to derive fundamental thermochemical quantities,including desorption and adsorption energies,reaction barrier heights,diffusion barrier heights,and lateral adsorbate interaction energies.Reaction mechanisms can also be revealed and reaction intermediates directly detected.The high time resolution of VRK al-lows study of catalytic reactions at the high temperatures typical of conditions present in real catalytic reactors.Current work exploiting the newest and by far the most powerful variant of VRK has only scratched the surface of what is possible,signifying a promising future for re-searchers in this field.展开更多
The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succini...The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.展开更多
Epithelial ovarian cancer(EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biologic...Epithelial ovarian cancer(EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biological markers(mRNA and proteins biomarkers), the mortality rate of ovarian cancer remains a challenge because of its late diagnosis, which is specifically attributed to low specificities and sensitivities. Under this compulsive scenario, recent advances in expression biology have shifted in identifying and developing specific and sensitive biomarkers, such as micro RNAs(miRNAs) for cancer diagnosis and prognosis. MiRNAs are a novel class of small non-coding RNAs that deregulate gene expression at the posttranscriptional level, either by translational repression or by mRNA degradation. These mechanisms may be involved in a complex cascade of cellular events associated with the pathophysiology of many types of cancer. MiRNAs are easily detectable in tissue and blood samples of cancer patients. Therefore, miRNAs hold good promise as potential biomarkers in ovarian cancer. In this review, we attempted to provide a comprehensive profile of key miRNAs involved in ovarian carcinoma to establish mi RNAs as more reliable non-invasive clinical biomarkers for early detection of ovarian cancer compared with protein and DNA biomarkers.展开更多
Pai, an arid forest in Sindh Province of Pakistan, is important for the environmental, social, economic development and conservation of ecosystems of the province. Considering the significance of the forest for Sindh ...Pai, an arid forest in Sindh Province of Pakistan, is important for the environmental, social, economic development and conservation of ecosystems of the province. Considering the significance of the forest for Sindh and the calls from the local population for its deforestation, we quantified the spatial and temporal variation in the vegetation of the forest and land surface temperature （LST） using optical and thermal Landsat satellite data. Our analysis of temporal （1987-2014） images with ArcGIS 10.1 revealed that the dense forest area was greatest at 725 ha （37 % of the total forest area） during 2013 while it was smallest at 217 ha （11%） in 1992. The sparse forest area peaked during 1987 at 1115 ha （58 %） under shrubs whereas it was smallest at 840 ha （43 %） in 1992, and the maximum deforestation of Pai forest occurred during 1992. Spatial change in vegetation over a period of about 27 years （1987-2014） revealed that vegetation increased on an area of 735 ha （37 %）, decreased on 427 ha （22 %）, and there was no change on 808 ha （41%） of the forest. Variation in temperature between shaded （dense forest） and unshaded areas （bare land） of the forest was from 6 to 10 ℃. While the temperature difference between areas with sparse forest and bare land ranged from 4 to 6℃. An inverse relationship between LST and NDVI of Pai forest with coefficients of determination of 0.944 and 0.917 was observed when NDVI was plotted against minimum and maximum LST, respectively. The vegetation in the forest increased with time and the areas of more dense Pai forest supported lower surface temperature and thus air temperature.展开更多
Titanium dioxide (TiO2) nano-particle is widely used in composite materials to its improved mechanical properties.TiO2 nano-particle was used in the composite material that consists of palm oil sludge from the palm oi...Titanium dioxide (TiO2) nano-particle is widely used in composite materials to its improved mechanical properties.TiO2 nano-particle was used in the composite material that consists of palm oil sludge from the palm oil production and activated sludge cake from a papermaking process.TiO2 was synthesized by a hydrolysis of titanium isopropoxide.The parameter was investigated by the mole ratio of reactant to different solvents (isopropanol and isobutanol).The solution was prepared by adjusting pH to acid solution,resulting in different sizes and distributions of precipitate which was heated at different temperatures.The obtained samples were then morphologically and structurally characterized using X-ray diffraction (XRD) and particle size distribution (PSD).The experimental results show that the TiO2 sample from isopropanol solvent with heated temperature of 600 °C exhibits the best results.Consequently,different mass fractions of TiO2 (0,0.5%,1.0%,2.0%,4.0% and 8.0%) were used for specimens that were made from palm oil sludge mixed with activated sludge cake.All samples were later characterized by 3-point bending test and compression test.The results indicate that the adding 0.5% and 1.0% TiO2 particles to the composite material outperforms the other fractions in terms of enhancing mechanical properties.Nonetheless,mechanical properties tends to decrease when adding 2.0% TiO2.展开更多
Bike sharing is considered a state-of-the-art transportation program. It is ideal for short or medium trips providing riders the ability to pick up a bike at any self-serve bike station and return it to any bike stati...Bike sharing is considered a state-of-the-art transportation program. It is ideal for short or medium trips providing riders the ability to pick up a bike at any self-serve bike station and return it to any bike station located within the system’s coverage area. The bike sharing programs in the United States are still very young compared to those in European countries. Washington DC was the first jurisdiction to devise a third generation bike sharing system in the US in 2008. To evaluate the popularity of a bike sharing program, a sentiment analysis of the riders’ feedback can be performed. Twitter is a great platform to understand people’s views instantly. Social media mining is, thus, gaining popularity in many research areas including transportation. Social media mining has two major advantages over conventional attitudinal survey methods—it can easily reach a large audience and it can reflect the true behavior of participants because of the anonymity social media provides. It is known that self-imposed censor is common in responding to conversational attitudinal surveys. This study performed text mining on the tweets related to a case study (Capital Bike share of Washington DC) to perform sentiment analysis or opinion mining. The results of the text mining mostly revealed higher positive sentiments towards the current system.展开更多
In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Conver...In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature.展开更多
Two-dimensional Fourier transform(2D FT) spectroscopy is an important technology that developed in recent decades and has many advantages over other ultrafast spectroscopy methods. Although 2D FT spectroscopy provides...Two-dimensional Fourier transform(2D FT) spectroscopy is an important technology that developed in recent decades and has many advantages over other ultrafast spectroscopy methods. Although 2D FT spectroscopy provides great opportunities for studying various complex systems, the experimental implementation and theoretical description of 2D FT spectroscopy measurement still face many challenges, which limits their wide application.Recently, the 2D FT spectroscopy reaches maturity due to many new developments which greatly reduces the technical barrier in the experimental implementation of the 2D FT spectrometer. There have been several different approaches developed for the optical design of the 2D FT spectrometer, each with its own advantages and limitations. Thus, a procedure to help an experimentalist to build a 2D FT spectroscopy experimental apparatus is needed.This tutorial review is intending to provide an accessible introduction for a beginner to build a 2D FT spectrometer.展开更多
We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of ...We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of M31. Here, we do photometric analysis of a faint W UMa binary CSS_JO04259.3＋410629 identified in the target field. The orbital period of this star is found to be 0.266402±0.000018 d. The photometric mass ratio, q, is found to be 0.28±0.01. The photometric light curves are investigated using the Wilson-Devinney （WD） code and absolute parameters are determined using empirical relations which provide masses and radii of the binary as M1 = 1.19±0.09M⊙, M2 = 0.33±0.02M⊙ and R1 = 1.02±0.04R⊙, R2 = 0.58±0.08Re respectively based on Rc band data. Quite similar values are found by analyzing/c band data. From the photometric light curve examination, the star is understood to be a low mass-ratio overcontact binary of A-subtype with a high fill-out factor of about 47%. The binary system is found to be located approximately at a distance of 2.64±0.03 kpc having a separation of 2.01 ±0.05 Re between the two components.展开更多
Electrochemical water splitting to produce hydrogen fuel is a promising renewable energy-conversion technique.Large-scale electrolysis of freshwater may deplete water resources and cause water scarcity worldwide.Thus,...Electrochemical water splitting to produce hydrogen fuel is a promising renewable energy-conversion technique.Large-scale electrolysis of freshwater may deplete water resources and cause water scarcity worldwide.Thus,seawater electrolysis is a potential solution to the future energy and water crisis.In seawater electrolysis,it is critical to develop cost-effective electrocatalysts to split seawater without chloride corrosion.Herein,we present zinc-doped nickel iron(oxy)hydroxide nanocubes passivated by negatively charged polyanions(NFZ-PBA-S)that exhibits outstanding catalytic activity,stability,and selectivity for seawater oxidation.Zn dopants and polyanion-rich passivated surface layers in NFZ-PBA-S could effectively repel chlorine ions and enhance corrosion resistance,enabling its excellent catalytic activity and stability for seawater oxidation.展开更多
We present a detailed analysis of the set theoretical proof of Wigner for Bell type inequalities with the following result. Wigner introduced a crucial assumption that is not related to Einstein’s local realism, but ...We present a detailed analysis of the set theoretical proof of Wigner for Bell type inequalities with the following result. Wigner introduced a crucial assumption that is not related to Einstein’s local realism, but instead, without justification, to the existence of certain joint probability measures for possible and actual measurement outcomes of Einstein-Podolsky-Rosen (EPR) experiments. His conclusions about Einstein’s local realism are, therefore, not applicable to EPR experiments and the contradiction of the experimental outcomes to Wigner’s results has no bearing on the validity of Einstein’s local realism.展开更多
We investigate two-leg Hubbard ladders in the Luttinger liquid regime by the density-matrix renormalization group method. Applicability of the bond concept in this region is discussed in a quantitative comparison of p...We investigate two-leg Hubbard ladders in the Luttinger liquid regime by the density-matrix renormalization group method. Applicability of the bond concept in this region is discussed in a quantitative comparison of power-law decay exponents, energy components and anti-bond occupations between ladders and chains. The interaction between bond and anti-bond bands induced by finite Hubbard repulsion U is emphasized by our numerical results. Our quantitative results are useful for the justification of the validity of various analytical approaches.展开更多
It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measur...It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measurement outcomes are considered. J. S. Bell and his followers have committed critical inaccuracies related to spin-gauge and probability measures of such subsets, because they use exclusively a single probability space for all data sets and sub-sets of data. It is also shown that Bell and followers use far too stringent epistemological requirements for the consequences of space-like separation. Their requirements reach way beyond Einstein’s separation principle and cannot be met by the major existing physical theories including relativity and even classical mechanics. For example, the independent free will does not empower the experimenters to choose multiple independent spin-gauges in the two EPRB wings. It is demonstrated that the suggestion of instantaneous influences at a distance (supposedly “derived” from experiments with entangled quantum entities) is a consequence of said inaccuracies and takes back rank as soon as the Kolmogorov probability measures are related to a consistent global spin-gauge and permitted to be different for different data subsets: Using statistical interpretations and different probability spaces for certain subsets of outcomes instead of probability amplitudes related to single quantum entities, permits physical explanations without a violation of Einstein’s separation principle.展开更多
Due to their complex structure,2-D models are challenging to work with;additionally,simulation,analysis,design,and control get increasingly difficult as the order of the model grows.Moreover,in particular time interva...Due to their complex structure,2-D models are challenging to work with;additionally,simulation,analysis,design,and control get increasingly difficult as the order of the model grows.Moreover,in particular time intervals,Gawronski and Juang’s time-limited model reduction schemes produce an unstable reduced-order model for the 2-D and 1-D models.Researchers revealed some stability preservation solutions to address this key flaw which ensure the stability of 1-D reduced-order systems;nevertheless,these strategies result in large approximation errors.However,to the best of the authors’knowledge,there is no literature available for the stability preserving time-limited-interval Gramian-based model reduction framework for the 2-D discrete-time systems.In this article,2-D models are decomposed into two separate sub-models(i.e.,two cascaded 1-D models)using the condition of minimal rank-decomposition.Model reduction procedures are conducted on these obtained two 1-D sub-models using limited-time Gramian.The suggested methodology works for both 2-D and 1-D models.Moreover,the suggested methodology gives the stability of the reduced model as well as a priori error-bound expressions for the 2-D and 1-D models.Numerical results and comparisons between existing and suggested methodologies are provided to demonstrate the effectiveness of the suggested methodology.展开更多
A classical theory for the Raman optical activity(ROA)is proposed based on a picture that for a normal mode,atoms of a molecule with partial residual charges act as oscillating dipoles around their equilibrium positio...A classical theory for the Raman optical activity(ROA)is proposed based on a picture that for a normal mode,atoms of a molecule with partial residual charges act as oscillating dipoles around their equilibrium positions,which also induce magnetic moments on the other atoms(dipoles),reciprocally.Then the resulting coupling between electric dipoles and magnetic moments of the molecule contributes to the optical activity.Despite its crude approximation,this model offers a physical essence for ROA and produces results that are of quality comparable to the complicated quantum-chemical calculation,as far as the sign of the circular intensity difference for the ROA is concerned.展开更多
The monolayers of a polymer liquid crystal at an air-water interface undergo successive phase transitions caused by conformation changes.In different phases,the polymer liquid crystal Langmuir-Blodgett (LB) films are ...The monolayers of a polymer liquid crystal at an air-water interface undergo successive phase transitions caused by conformation changes.In different phases,the polymer liquid crystal Langmuir-Blodgett (LB) films are prepared to align liquid crystals homeotropically.The alignment property of the LB films is independent of the conformational changes of aligning agents.展开更多
An improved sputtering method,which is named "in situ oxidizing sputtering",was used to prepare periodic Ni/NiO multilayers.Samples studied in this letter contains 20 pairs of Ni/NiO with period about 100 A....An improved sputtering method,which is named "in situ oxidizing sputtering",was used to prepare periodic Ni/NiO multilayers.Samples studied in this letter contains 20 pairs of Ni/NiO with period about 100 A.In Raman scattering,the low frequency phonon modes are hiterpreted as LA phonon folding effect,which is usually measured in superlattices with a strict periodic structure.The ferromagnetic resonance spectra were also recorded at room temperature with microwave frequency 9.777 GHz.The analysis of spin wave resonance indicates that Ni sublayers are coupled with each other,which is the mechanism that surely relates to the amorphous-like NiO spacers.展开更多
A model for the squeezed output coupler of the trapped Bose-Einstein condensed atoms is established with a simple many-boson system of two states with linear coupling, by preparing an initially squeezed light field. I...A model for the squeezed output coupler of the trapped Bose-Einstein condensed atoms is established with a simple many-boson system of two states with linear coupling, by preparing an initially squeezed light field. In the Bogoliubov approximation, its solutions show that the quadrature squeezing effect mutually oscillates between the coupling light field and the output atomic field. This manifests that the initially squeezed light will transform into a coherent state after some period of coupling interaction while the output atomic field is in a squeezed state.展开更多
基金support from the National Natural Science Foundation of China(NSFC,Grant No.52175341)Shandong Provincial Natural Science Foundation(Grant No.ZR2022JQ24)Funding Project of Jinan City’s New Twenty Items for Colleges and Universities(Grant No.202333038).
文摘Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum-assisted filtration.Interestingly,within the polytetrafluoroethylene(PTFE)-carbon nanotube(CNT)-Fe_(3)O_(4)layer(FCFe),CNT nanofibers interweave with PTFE fibers to form a stable“silk-like”structure that effectively captures Fe_(3)O_(4)particles.By incorporating a highly conductive MXene layer,the FCFe/MXene(FCFe/M)membrane exhibits excellent electrical/thermal conductivity,mechanical properties,and flame retardancy.Impressively,benefiting from the rational regulation of component proportions and the design of a Janus structure,the FCFe/M membrane with a thickness of only 84.9μm delivers outstanding EMI shielding effectiveness of 44.56 dB in the X-band,with a normalized specific SE reaching 10,421.3 dB cm^(2)g^(-1),which is attributed to the“absorption-reflection-reabsorption”mechanism.Furthermore,the membrane demonstrates low-voltage-driven Joule heating and fast-response photothermal performance.Under the stimulation of a 3 V voltage and an optical power density of 320 mW cm^(-2),the surface temperatures of the FCFe/M membranes can reach up to 140.4 and 145.7℃,respectively.In brief,the FCFe/M membrane with anti-electromagnetic radiation and temperature regulation is an attractive candidate for the next generation of wearable electronics,EMI compatibility,visual heating,thermotherapy,and military and aerospace applications.
基金financially supported by the National Natu-ral Science Foundation of China(Nos.U24A20204,22168016,and 22278101)the Innovation Project for Scientific and Technological Talents in Hainan Province(No.KJRC2023C08)the Innovation Research Team in Hainan Province(No.525CXTD607).
文摘Electromagnetic wave(EMW)absorbers with anti-corrosion property are highly desired to enhance the durability of military targets in harsh condition.Herein,cross-link NiAl-layered double hydroxide(NiAl-LDH)nanosheets on the inner/outer surfaces of carbon microtubes(CMTs)are ingeniously constructed through the combination of atomic layer deposition technique and a hydrothermal method.The obtained NiAl-LDH/CMT composite exhibits excellent EMW absorption and corrosion resistance performance.The large internal cavity of CMT significantly enhances impedance matching.The uniform distribution of NiAl-LDH nanosheets on both the inner and outer surfaces of CMT generates numerous heterogeneous inter-faces that induce substantial polarization loss.Consequently,at a filler rate of only 5 wt.%,the NiAl-LDH/CMT composite exhibits a minimum reflection loss of−60.2 dB and a maximum effective absorp-tion bandwidth of 5.9 GHz.In addition,the combined high impermeability of CMT and the effective Cl^(-)-trapping ability of NiAl-LDH endows NiAl-LDH/CMT composite with outstanding corrosion protection property in simulated seawater environment.Furthermore,the PO_(4)^(3-)anions are effectively incorporated into the NiAl-LDH interlayer via anion exchange,which can further enhance corrosion protection capac-ity through surface inactivation from slow-release PO_(4)^(3-)anions without reducing their EMW absorption performance.In summary,this work can give guidance for the development of efficient anti-corrosion EMW absorption materials.
基金support from the Alexander von Humboldt foundationsupport from the National Natural Science Foundation of China(No.22473077)+2 种基金support from the BENCh graduate school,funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)389479699/GRK2455support from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme grant agreement No.[833404]support from CRC 1633 Proton Coupled Electron Transfer,Project C02。
文摘Heterogeneous catalysis on solid surfaces provides high-value chemicals and is involved in a large fraction of the world’s economic productivity,yet our understanding of this important class of processes remains limited.Thermal reaction rates obtained from experiments on mod-el catalysts provide quantitative data that can reveal reaction mechanisms and provide benchmarks for computational simulations of catalytic processes.This perspective describes a critical advance in measuring these rates:velocity resolved kinetics(VRK).VRK delivers ab-solute rates for elementary surface reactions that are of sufficient accuracy that they may be meaningfully compared to theoretical rate predictions,creating a powerful synergy between theory and experiment.It is now routinely possible to derive fundamental thermochemical quantities,including desorption and adsorption energies,reaction barrier heights,diffusion barrier heights,and lateral adsorbate interaction energies.Reaction mechanisms can also be revealed and reaction intermediates directly detected.The high time resolution of VRK al-lows study of catalytic reactions at the high temperatures typical of conditions present in real catalytic reactors.Current work exploiting the newest and by far the most powerful variant of VRK has only scratched the surface of what is possible,signifying a promising future for re-searchers in this field.
基金supported by the Institutional Research Grant(Thailand Research Fund:IRG598004)
文摘The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.
基金the ICMR New Delhi for financial support (Grant No. 3/2/2/136/2012/NCD-Ⅲ)
文摘Epithelial ovarian cancer(EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biological markers(mRNA and proteins biomarkers), the mortality rate of ovarian cancer remains a challenge because of its late diagnosis, which is specifically attributed to low specificities and sensitivities. Under this compulsive scenario, recent advances in expression biology have shifted in identifying and developing specific and sensitive biomarkers, such as micro RNAs(miRNAs) for cancer diagnosis and prognosis. MiRNAs are a novel class of small non-coding RNAs that deregulate gene expression at the posttranscriptional level, either by translational repression or by mRNA degradation. These mechanisms may be involved in a complex cascade of cellular events associated with the pathophysiology of many types of cancer. MiRNAs are easily detectable in tissue and blood samples of cancer patients. Therefore, miRNAs hold good promise as potential biomarkers in ovarian cancer. In this review, we attempted to provide a comprehensive profile of key miRNAs involved in ovarian carcinoma to establish mi RNAs as more reliable non-invasive clinical biomarkers for early detection of ovarian cancer compared with protein and DNA biomarkers.
文摘Pai, an arid forest in Sindh Province of Pakistan, is important for the environmental, social, economic development and conservation of ecosystems of the province. Considering the significance of the forest for Sindh and the calls from the local population for its deforestation, we quantified the spatial and temporal variation in the vegetation of the forest and land surface temperature （LST） using optical and thermal Landsat satellite data. Our analysis of temporal （1987-2014） images with ArcGIS 10.1 revealed that the dense forest area was greatest at 725 ha （37 % of the total forest area） during 2013 while it was smallest at 217 ha （11%） in 1992. The sparse forest area peaked during 1987 at 1115 ha （58 %） under shrubs whereas it was smallest at 840 ha （43 %） in 1992, and the maximum deforestation of Pai forest occurred during 1992. Spatial change in vegetation over a period of about 27 years （1987-2014） revealed that vegetation increased on an area of 735 ha （37 %）, decreased on 427 ha （22 %）, and there was no change on 808 ha （41%） of the forest. Variation in temperature between shaded （dense forest） and unshaded areas （bare land） of the forest was from 6 to 10 ℃. While the temperature difference between areas with sparse forest and bare land ranged from 4 to 6℃. An inverse relationship between LST and NDVI of Pai forest with coefficients of determination of 0.944 and 0.917 was observed when NDVI was plotted against minimum and maximum LST, respectively. The vegetation in the forest increased with time and the areas of more dense Pai forest supported lower surface temperature and thus air temperature.
基金the Graduate School Kasetsart Universitythe Office of the National Research Council of Thailand for their financial support under a research plan "Increase the value through the production of agriculture"
文摘Titanium dioxide (TiO2) nano-particle is widely used in composite materials to its improved mechanical properties.TiO2 nano-particle was used in the composite material that consists of palm oil sludge from the palm oil production and activated sludge cake from a papermaking process.TiO2 was synthesized by a hydrolysis of titanium isopropoxide.The parameter was investigated by the mole ratio of reactant to different solvents (isopropanol and isobutanol).The solution was prepared by adjusting pH to acid solution,resulting in different sizes and distributions of precipitate which was heated at different temperatures.The obtained samples were then morphologically and structurally characterized using X-ray diffraction (XRD) and particle size distribution (PSD).The experimental results show that the TiO2 sample from isopropanol solvent with heated temperature of 600 °C exhibits the best results.Consequently,different mass fractions of TiO2 (0,0.5%,1.0%,2.0%,4.0% and 8.0%) were used for specimens that were made from palm oil sludge mixed with activated sludge cake.All samples were later characterized by 3-point bending test and compression test.The results indicate that the adding 0.5% and 1.0% TiO2 particles to the composite material outperforms the other fractions in terms of enhancing mechanical properties.Nonetheless,mechanical properties tends to decrease when adding 2.0% TiO2.
文摘Bike sharing is considered a state-of-the-art transportation program. It is ideal for short or medium trips providing riders the ability to pick up a bike at any self-serve bike station and return it to any bike station located within the system’s coverage area. The bike sharing programs in the United States are still very young compared to those in European countries. Washington DC was the first jurisdiction to devise a third generation bike sharing system in the US in 2008. To evaluate the popularity of a bike sharing program, a sentiment analysis of the riders’ feedback can be performed. Twitter is a great platform to understand people’s views instantly. Social media mining is, thus, gaining popularity in many research areas including transportation. Social media mining has two major advantages over conventional attitudinal survey methods—it can easily reach a large audience and it can reflect the true behavior of participants because of the anonymity social media provides. It is known that self-imposed censor is common in responding to conversational attitudinal surveys. This study performed text mining on the tweets related to a case study (Capital Bike share of Washington DC) to perform sentiment analysis or opinion mining. The results of the text mining mostly revealed higher positive sentiments towards the current system.
基金the Natural Science Foundation of China(Grant Nos.61673169,11301127,11701176,11626101,and 11601485)The Natural Science Foundation of Huzhou City(Grant No.2018YZ07).
文摘In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature.
基金the National Natural Science Foundation of China(No.91753118 and No.21773012)the Fundamental Research Funds for Central Universities。
文摘Two-dimensional Fourier transform(2D FT) spectroscopy is an important technology that developed in recent decades and has many advantages over other ultrafast spectroscopy methods. Although 2D FT spectroscopy provides great opportunities for studying various complex systems, the experimental implementation and theoretical description of 2D FT spectroscopy measurement still face many challenges, which limits their wide application.Recently, the 2D FT spectroscopy reaches maturity due to many new developments which greatly reduces the technical barrier in the experimental implementation of the 2D FT spectrometer. There have been several different approaches developed for the optical design of the 2D FT spectrometer, each with its own advantages and limitations. Thus, a procedure to help an experimentalist to build a 2D FT spectroscopy experimental apparatus is needed.This tutorial review is intending to provide an accessible introduction for a beginner to build a 2D FT spectrometer.
基金financial support from the project DST/INT/SA/P-02financial support from the project UGC-BSR research Start-Up Grant Sanctioned vide UGC Order No. F. 30-108/2015(BSR) of UGC
文摘We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of M31. Here, we do photometric analysis of a faint W UMa binary CSS_JO04259.3＋410629 identified in the target field. The orbital period of this star is found to be 0.266402±0.000018 d. The photometric mass ratio, q, is found to be 0.28±0.01. The photometric light curves are investigated using the Wilson-Devinney （WD） code and absolute parameters are determined using empirical relations which provide masses and radii of the binary as M1 = 1.19±0.09M⊙, M2 = 0.33±0.02M⊙ and R1 = 1.02±0.04R⊙, R2 = 0.58±0.08Re respectively based on Rc band data. Quite similar values are found by analyzing/c band data. From the photometric light curve examination, the star is understood to be a low mass-ratio overcontact binary of A-subtype with a high fill-out factor of about 47%. The binary system is found to be located approximately at a distance of 2.64±0.03 kpc having a separation of 2.01 ±0.05 Re between the two components.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF)funded by the Ministry of Science,ICT and Future Planning (2021R1A2C2091497 and 2022R1A2C2010162)supported by“Regional Innovation Strategy (RIS)”through the National Research Foundation of Korea (NRF)funded by the Ministry of Education (MOE) (2022RIS-005)+1 种基金supported by the Ministry of Trade,Industry,and Energy (20018145)supported by KIST Institutional Program (Project Nos.2V09781)。
文摘Electrochemical water splitting to produce hydrogen fuel is a promising renewable energy-conversion technique.Large-scale electrolysis of freshwater may deplete water resources and cause water scarcity worldwide.Thus,seawater electrolysis is a potential solution to the future energy and water crisis.In seawater electrolysis,it is critical to develop cost-effective electrocatalysts to split seawater without chloride corrosion.Herein,we present zinc-doped nickel iron(oxy)hydroxide nanocubes passivated by negatively charged polyanions(NFZ-PBA-S)that exhibits outstanding catalytic activity,stability,and selectivity for seawater oxidation.Zn dopants and polyanion-rich passivated surface layers in NFZ-PBA-S could effectively repel chlorine ions and enhance corrosion resistance,enabling its excellent catalytic activity and stability for seawater oxidation.
文摘We present a detailed analysis of the set theoretical proof of Wigner for Bell type inequalities with the following result. Wigner introduced a crucial assumption that is not related to Einstein’s local realism, but instead, without justification, to the existence of certain joint probability measures for possible and actual measurement outcomes of Einstein-Podolsky-Rosen (EPR) experiments. His conclusions about Einstein’s local realism are, therefore, not applicable to EPR experiments and the contradiction of the experimental outcomes to Wigner’s results has no bearing on the validity of Einstein’s local realism.
基金Supported by the National Natural Science Foundation of China under Grant No 10447119.
文摘We investigate two-leg Hubbard ladders in the Luttinger liquid regime by the density-matrix renormalization group method. Applicability of the bond concept in this region is discussed in a quantitative comparison of power-law decay exponents, energy components and anti-bond occupations between ladders and chains. The interaction between bond and anti-bond bands induced by finite Hubbard repulsion U is emphasized by our numerical results. Our quantitative results are useful for the justification of the validity of various analytical approaches.
文摘It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measurement outcomes are considered. J. S. Bell and his followers have committed critical inaccuracies related to spin-gauge and probability measures of such subsets, because they use exclusively a single probability space for all data sets and sub-sets of data. It is also shown that Bell and followers use far too stringent epistemological requirements for the consequences of space-like separation. Their requirements reach way beyond Einstein’s separation principle and cannot be met by the major existing physical theories including relativity and even classical mechanics. For example, the independent free will does not empower the experimenters to choose multiple independent spin-gauges in the two EPRB wings. It is demonstrated that the suggestion of instantaneous influences at a distance (supposedly “derived” from experiments with entangled quantum entities) is a consequence of said inaccuracies and takes back rank as soon as the Kolmogorov probability measures are related to a consistent global spin-gauge and permitted to be different for different data subsets: Using statistical interpretations and different probability spaces for certain subsets of outcomes instead of probability amplitudes related to single quantum entities, permits physical explanations without a violation of Einstein’s separation principle.
文摘Due to their complex structure,2-D models are challenging to work with;additionally,simulation,analysis,design,and control get increasingly difficult as the order of the model grows.Moreover,in particular time intervals,Gawronski and Juang’s time-limited model reduction schemes produce an unstable reduced-order model for the 2-D and 1-D models.Researchers revealed some stability preservation solutions to address this key flaw which ensure the stability of 1-D reduced-order systems;nevertheless,these strategies result in large approximation errors.However,to the best of the authors’knowledge,there is no literature available for the stability preserving time-limited-interval Gramian-based model reduction framework for the 2-D discrete-time systems.In this article,2-D models are decomposed into two separate sub-models(i.e.,two cascaded 1-D models)using the condition of minimal rank-decomposition.Model reduction procedures are conducted on these obtained two 1-D sub-models using limited-time Gramian.The suggested methodology works for both 2-D and 1-D models.Moreover,the suggested methodology gives the stability of the reduced model as well as a priori error-bound expressions for the 2-D and 1-D models.Numerical results and comparisons between existing and suggested methodologies are provided to demonstrate the effectiveness of the suggested methodology.
文摘A classical theory for the Raman optical activity(ROA)is proposed based on a picture that for a normal mode,atoms of a molecule with partial residual charges act as oscillating dipoles around their equilibrium positions,which also induce magnetic moments on the other atoms(dipoles),reciprocally.Then the resulting coupling between electric dipoles and magnetic moments of the molecule contributes to the optical activity.Despite its crude approximation,this model offers a physical essence for ROA and produces results that are of quality comparable to the complicated quantum-chemical calculation,as far as the sign of the circular intensity difference for the ROA is concerned.
基金Supported by the National Natural Science Foundation of China
文摘The monolayers of a polymer liquid crystal at an air-water interface undergo successive phase transitions caused by conformation changes.In different phases,the polymer liquid crystal Langmuir-Blodgett (LB) films are prepared to align liquid crystals homeotropically.The alignment property of the LB films is independent of the conformational changes of aligning agents.
基金Supported by the National Natural Science Foundation of Chinathe National Advanced Materials Committee of China。
文摘An improved sputtering method,which is named "in situ oxidizing sputtering",was used to prepare periodic Ni/NiO multilayers.Samples studied in this letter contains 20 pairs of Ni/NiO with period about 100 A.In Raman scattering,the low frequency phonon modes are hiterpreted as LA phonon folding effect,which is usually measured in superlattices with a strict periodic structure.The ferromagnetic resonance spectra were also recorded at room temperature with microwave frequency 9.777 GHz.The analysis of spin wave resonance indicates that Ni sublayers are coupled with each other,which is the mechanism that surely relates to the amorphous-like NiO spacers.
文摘A model for the squeezed output coupler of the trapped Bose-Einstein condensed atoms is established with a simple many-boson system of two states with linear coupling, by preparing an initially squeezed light field. In the Bogoliubov approximation, its solutions show that the quadrature squeezing effect mutually oscillates between the coupling light field and the output atomic field. This manifests that the initially squeezed light will transform into a coherent state after some period of coupling interaction while the output atomic field is in a squeezed state.
