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81.
Cancer remains an intractable medical problem. Rapid diagnosis and identification of cancer are critical to differentiate it from nonmalignant diseases. High-throughput biofluid metabolic analysis has potential for cancer diagnosis. Nevertheless, the present metabolite analysis method does not meet the demand for high-throughput screening of diseases. Herein, a high-throughput, cost-effective, and noninvasive urine metabolic profiling method based on TiO2/MXene-assisted laser desorption/ionization mass spectrometry (LDI-MS) is presented for the efficient screening of bladder cancer (BC) and nonmalignant urinary disease. Combined with machine learning, TiO2/MXene-assisted LDI-MS enables high diagnostic accuracy (96.8%) for the classification of patient groups (including 47 BC and 46 ureteral calculus (UC) patients) from healthy controls (113 cases). In addition, BC patients can also be identified from noncancerous UC individuals with an accuracy of 88.3% in the independent test cohort. Furthermore, metabolite variations between BC and UC individuals are investigated based on relative quantification, and related pathways are also discussed. These results suggest that this method, based on urine metabolic patterns, provides a potential tool for rapidly distinguishing urinary diseases and it may pave the way for precision medicine.  相似文献   
82.
通过优化成分设计以及轧制、热处理工艺,成功开发出8 ~ 80 mm厚度的免涂装低屈强比耐候桥梁钢.针对免涂装低屈强比耐候桥梁钢的工艺、金相组织和焊接性进行分析研究,结果表明:耐候桥梁钢Q345qENH~ Q690qENH的屈强比可以通过适量铁素体+不同形态贝氏体组织配比进行调控,使低温冲击韧性、低屈强比和耐候性同时得到保证,实现了优良的强度、冲击韧性和可焊性.  相似文献   
83.
Pulsed laser deposition (PLD) was used to prepare tungsten trioxide (WO3) films on ITO substrates with a varying laser power density of 4.0–5.5 W/cm2. XPS indicated that when the laser power density decreased, the peak positions of the W 4f and O 1s orbits shifted slightly to low energy due to the difference in oxygen vacancies. As the laser power density decreased, W6+ gradually replaced the lattice position of O2?, increasing oxygen vacancies in the lattice. The transmittance modulated values (ΔT) were over 44% at 830 nm, indicating strong absorption by the WO3 thin films in the near-infrared ray. The switching time of the WO3 thin films between bleached states and coloured states decreased as the laser power density increased due to the amorphous structure, morphology, and lower oxygen deficiency at a high power density. The high ΔT and very fast switching time of tb (1.09 s) and tc (6.01 s) demonstrated the excellent electrochromic (EC) properties of the WO3 films prepared by PLD.  相似文献   
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86.
In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration showed negligible effect on efficiencies for removal of nitrate and COD.However,the ammonium ions removal rate was moderately reduced,when the influent SMX concentration in wastewater reached 6 mg/L.Total nitrogen removal efficiency remained as high as 76.77%towards the day 158 at the end of experiment.Candidatus_Brocadia and Candidatus_Kuenenia were the functional anammox strains.The unclassified_f__Rhodobacteraceae sp.was predominant heterotrophic denitrifying strain in the studied reactor.The concentrations of soluble extracellular polymeric substances in sludge obviously increased from 16.76 mg/g VSS to 32.31 mg/g VSS,which might protect the nitrogen removal strains from high-concentration SMX.This result provides a theoretical and technical foundation for the application of denitrifying ammonium oxidation process in treating sulfamethoxazole-laden secondary wastewater effluent.  相似文献   
87.
To gain insight into the ageing behavior of ultrafine grain(UFG)structure,the precipitation phenom-ena and microstructural evolutions of Mg-6Zn-1Y-0.4Ce-0.5 Zr(wt.%)alloy processed by sliding friction treatment(SFT)were systematically studied using hardness texting,transmission electron microscopy(TEM)equipped with high-angle annular dark-field scanning(HADDF-STEM),X-ray diffraction(XRD)and XRD line broadening analysis.The microhardness of the SFT-processed(SFTed)sample initially decreases from 109.6 HV to 104.8 HV at ageing for 8 h,and then increases to the peak-ageing point of 115.4 HV at 16 h.Subsequently,it enters the over-aged period.The un-SFTed sample,as the counterpart,follows a regular ageing behavior that increases from 89.9 HV to 99.6 HV when ageing for 12 h,and then drops.A multi-mechanistic model is established to describe the strengthening due to grain refinement,disloca-tion accumulation,precipitation etc.The analysis reveals that the temperature sensitive UFG structure has an obvious grain coarsening effect,which arouses the soft phenomenon in the early ageing stage.But precipitation hardening provides an excellent hardness enhancement for overcoming the negative influ-ence and helping to reach the peak-aged point.In our microstructural observations,a lot of equilibrium ultrafine MgZn2 precipitates precipitate along dislocations because defects can provide the favorable conditions for the migration and segregation of solute atoms.  相似文献   
88.
The direct-synthesis of conductive PbS quantum dot (QD) ink is facile, scalable, and low-cost, boosting the future commercialization of optoelectronics based on colloidal QDs. However, manipulating the QD matrix structures still is a challenge, which limits the corresponding QD solar cell performance. Here, for the first time a coordination-engineering strategy to finely adjust the matrix thickness around the QDs is presented, in which halogen salts are introduced into the reaction to convert the excessive insulating lead iodide into soluble iodoplumbate species. As a result, the obtained QD film exhibits shrunk insulating shells, leading to higher charge carrier transport and superior surface passivation compared to the control devices. A significantly improved power-conversion efficiency from 10.52% to 12.12% can be achieved after the matrix engineering. Therefore, the work shows high significance in promoting the practical application of directly synthesized PbS QD inks in large-area low-cost optoelectronic devices.  相似文献   
89.
Copper catalysts are widely studied for the electroreduction of carbon dioxide (CO2) to value-added hydrocarbon products. Controlling the surface composition of copper nanomaterials may provide the electronic and structural properties necessary for carbon-carbon coupling, thus increasing the Faradaic efficiency (FE) towards ethylene and other multi-carbon (C2+) products. Synthesis and catalytic study of silver-coated copper nanoparticles (Cu@Ag NPs) for the reduction of CO2 are presented. Bimetallic CuAg NPs are typically difficult to produce due to the bulk immiscibility between these two metals. Slow injection of the silver precursor, concentrations of organic capping agents, and gas environment proved critical to control the size and metal distribution of the Cu@Ag NPs. The optimized Cu@Ag electrocatalyst exhibited a very low onset cell potential of −2.25 V for ethylene formation, reaching a FE towards C2+ products (FEC2+) of 43% at −2.50 V, which is 1.0 V lower than a reference Cu catalyst to reach a similar FEC2+. The high ethylene formation at low potentials is attributed to enhanced C C coupling on the Ag enriched shell of the Cu@Ag electrocatalysts. This study offers a new catalyst design towards increasing the efficiency for the electroreduction of CO2 to value-added chemicals.  相似文献   
90.
The quantitative optical measurement of deep sub-wavelength features with sub-nanometer sensitivity addresses the measurement challenge in the semiconductor fabrication process. Optical scatterings from the sidewalls of patterned devices reveal abundant structural and material information. We demonstrated a parametric indirect microscopic imaging (PIMI) technique that enables recovery of the profile of wavelength-scale objects with deep sub-wavelength resolution, based on measuring and filtering the variations of far-field scattering intensities when the illumination was modulated. The finite-difference time-domain (FDTD) numerical simulation was performed, and the experimental results were compared with atomic force microscopic (AFM) images to verify the resolution improvement achieved with PIMI. This work may provide a new approach to exploring the detailed structure and material properties of sidewalls and edges in semiconductor-patterned devices with enhanced contrast and resolution, compared with using the conventional optical microscopy, while retaining its advantage of a wide field of view and relatively low cost.  相似文献   
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