Broad area quantum cascade lasers(BA QCLs)have significant applications in many areas,but suffer from demanding pulse operating conditions and poor beam quality due to heat accumulation and generation of high order mo...
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Broad area quantum cascade lasers(BA QCLs)have significant applications in many areas,but suffer from demanding pulse operating conditions and poor beam quality due to heat accumulation and generation of high order modes.A structure of mini-array is adopted to improve the heat dissipation capacity and beam quality of BA *** active region is etched to form a multi-emitter and the channels are filled with In P:Fe,which acts as a lateral heat dissipation channel to improve the lateral heat dissipation efficiency.A device withλ~4.8μm,a peak output power of 122 W at 1.2%duty cycle with a pulse of 1.5μs is obtained in room temperature,with far-field single-lobed *** result allows BA QCLs to obtain high peak power at wider pump pulse widths and higher duty cycle conditions,promotes the application of the mid-infrared laser operating in pulsed mode in th e field of standoff photoacoustic chemical detection,space optical communication,and so on.
All-solid-state lithium batteries（ASSLBs） are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic *** solid-solid contact between lithium metal and solid ele...
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All-solid-state lithium batteries（ASSLBs） are strongly considered as the next-generation energy storage devices for their high energy density and intrinsic *** solid-solid contact between lithium metal and solid electrolyte plays a vital role in the performance of working ASSLBs,which is challenging to investigate quantitatively by experimental *** work proposed a quantitative model based on the finite element method for electrochemical impedance spectroscopy simulation of different solid-solid contact states in *** the assistance of an equivalent circuit model and distribution of relaxation times,it is discovered that as the number of voids and the sharpness of cracks increase,the contact resistance Rcgrows and ultimately dominates the battery *** accurate fitting,inverse proportional relations between contact resistance Rcand（1-porosity） as well as crack angle was *** contribution affords a fresh insight into clarifying solid-solid contact states in ASSLBs.
Non-centrosymmetric material systems can generate spontaneous photocurrent without a p-n junction under uniform illumination, which is known as the bulk photovoltaic effect（BPVE）. It has garnered significant attenti...
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Non-centrosymmetric material systems can generate spontaneous photocurrent without a p-n junction under uniform illumination, which is known as the bulk photovoltaic effect（BPVE）. It has garnered significant attention for its application potential in the fields of energy harvesting and photoelectric detection. In this study, we report the BPVE observed in twodimensional ferroelectric α-In2Se3multilayer flakes. The reversal in spontaneous photocurrent polarity is observed and associated with the out-of-plane ferroelectric polarization direction. The spontaneous photocurrent originating from the shift current is also polarization-sensitive. The amplitude of spontaneous photocurrent is further increased by one order of magnitude through vacuum annealing. Our results provide a further application potential for new-generation photodetectors based on BPVE with low power consumption and multi-dimensional optoelectronic detection.
OBJECTIVE: To investigate the difference in gut microbiota between population with damp-heat constitution(DHC) and balanced constitution(BC). METHODS: A multi-centered cross-sectional casecontrol study was conducted, ...
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OBJECTIVE: To investigate the difference in gut microbiota between population with damp-heat constitution(DHC) and balanced constitution(BC). METHODS: A multi-centered cross-sectional casecontrol study was conducted, which included 249 participants with damp-heat constitution or balanced constitution. Baseline information of participants was collected, and stool samples were collected for gut microbiota analysis. Principal coordinate analysis, linear discriminant analysis effect size analysis, receiver operating characteristic, random forest model, and phylogenetic investigation of communities by reconstruction of unobserved states methods were used to reveal the relationship between gut microbiota and the damp-heat constitution. RESULTS: Compared to those in the BC group, the richness and diversity of the microbiota, specifically those of several short-chain fatty acid producing genera such as Barnesiella, Coprobacter, and Butyricimonas, were significantly decreased in the DHC group. Regarding biological functions, flavonoid biosynthesis, propanoate metabolism, and nucleotide sugar metabolism were suppressed, while arachidonic acid metabolism and glutathione metabolism were enriched in the DHC group. Finally, a classifier based on the microbiota was constructed to discriminate between the DHC and BC populations. CONCLUSION: The gut microbiota of the DHC population exhibits significantly reduced diversity and is closely related to inflammation, metabolic disorders, and liver steatosis, which is consistent with clinical observations, thus serving as a potential diagnostic tool for traditional Chinese medicine constitution discrimination.
Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle ***,green and effective recycling methods are needed because LIBs contain h...
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Lithium-ion batteries(LIBs)are the most popular energy storage devices due to their high energy density,high operating voltage,and long cycle ***,green and effective recycling methods are needed because LIBs contain heavy metals such as Co,Ni,and Mn and organic compounds inside,which seriously threaten human health and the *** this work,we review the current status of spent LIB recycling,discuss the traditional pyrometallurgical and hydrometallurgical recovery processes,and summarize the existing short-process recovery technologies such as salt-assisted roasting,flotation processes,and direct ***,we analyze the problems and potential research prospects of the current recycling process,and point out that the multidisciplinary integration of recycling will become the mainstream technology for the development of spent LIBs.
Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a curren...
Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 ℃ and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.
In this paper， a novel method combining orthogonal polarization laser self-mixing interference is proposed. The method utilizes a rotating cuvette to measure the refractive index of liquids at different concentration...
In this paper， a novel method combining orthogonal polarization laser self-mixing interference is proposed. The method utilizes a rotating cuvette to measure the refractive index of liquids at different concentrations. The cuvette is filled with the liquid to be measured and rotated by a certain angle. The change in the number of interference fringes， caused by comparing an empty cuvette with a liquid-filled cuvette， is used to calculate the refractive index of the liquid. A four-fold logic subdivision algorithm is then used to improve measurement resolution. The experimental results show that for pure water and different NaCl and glucose solutions concentrations， the average relative errors are 0.47%， 0.59%， and 2.17%， respectively， with the maximum relative error within ±2.54%. The standard deviation of all solutions is less than 3.4%.
AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing ***:This study recruited 216 participants(216 eyes)from April 2022 to July *** the condition of no an...
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AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing ***:This study recruited 216 participants(216 eyes)from April 2022 to July *** the condition of no antibiotic use prior to cataract surgery,sterile swabs were used to collect samples from the lower conjunctival *** cultures were then conducted,followed by species identification through 16S rDNA gene *** factors associated with positive or negative bacterial isolation rates were analyzed,including age,gender,meibomian gland dysfunction(MGD),history of hypertension,history of diabetes,history of cancer,history of infectious diseases and the habit of wearing ***:Among the 216 eyes,78 eyes yielded isolates,with an isolation rate of 36.11%,detecting a total of 122 ***-positive rods accounted for 49.18%(60 strains),gram-positive cocci accounted for 45.08%(55 strains),gram-negative bacteria accounted for 4.92%(6 strains),and fungi accounted for 0.82%(1 strain).This study found that the most abundant genera in the conjunctival sac were Corynebacterium(42.62%),Staphylococcus(31.15%),Micrococcus(9.84%),Acinetobacter(4.10%),and Bacillus(3.28%).Furthermore,age(P=0.006),gender(P=0.039),diabetes(P=0.003),history of infectious diseases(P=0.02),and duration of mask replacement(Pjunctival *** hypertensive patients exhibited a higher isolation rate of conjunctival bacteria,it did not reach statistical significance,and the history of cancer did not affect the isolation rate of the conjunctival microbial community in cataract patients before ***:Potential changes are observed in the conjunctival microbiota among a sample of middleaged and elderly individuals from Beijing,***,an increased isolation rate of Corynebacterium and Micrococcus is detected,suggesting a possible change in the mic
The Fenton-like reaction between Cu^(2+)and H_(2)O_(2)was employed in chemical mechanical polishing to achieve efficient and high-quality processing of *** microstructure evolution and material removal rate of tungste...
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The Fenton-like reaction between Cu^(2+)and H_(2)O_(2)was employed in chemical mechanical polishing to achieve efficient and high-quality processing of *** microstructure evolution and material removal rate of tungsten during polishing process were investigated via scanning electron microscopy,X-ray photoelectron spectroscopy,ultraviolet−visible spectrophotometry,and electrochemical *** passivation behavior and material removal mechanism were *** show that the use of mixed H_(2)O_(2)+Cu(NO_(3))_(2)oxidant can achieve higher polishing efficiency and surface quality compared with the single oxidant Cu(NO_(3))_(2)or H_(2)O_(2).The increase in material removal rate is attributed to the rapid oxidation of W into WO_(3)via the chemical reaction between the substrate and hydroxyl radicals produced by the Fenton-like *** addition,material removal rate and static etch rate exhibit significantly different dependencies on the concentration of Cu(NO_(3))_(2),while the superior oxidant for achieving the balance between polishing efficiency and surface quality is 0.5 wt.%H_(2)O_(2)+1.0 wt.%Cu(NO_(3))_(2).
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