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We have developed a photocatalyst-free reaction system that uses Hantzsch esters as photoreducing agents to promote the coupling of carbonyl compounds to 1,2-diols. The system fully utilizes the single electron transfer and proton donor roles of Hantzsch esters. The system shows a wide range of substrate application. Aromatic ketones, aliphatic ketones, and aldehydes can be applied to the catalytic system. Both self-coupling and cross-coupling can achieve ideal results.
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Line edge roughness (LER) has been an important issue in the nanofabrication research, especially in integrated circuits. Despite numerous research studies has made efforts on achieving smaller LER value, a strategy to achieve sub-nanometer level LER still remain challenging due to inability to deposit energy with a profile of sub-nanometer LER. In this work, we use scanning helium ion beam to expose hydrogen silsesquioxane (HSQ) resist on SiNx membrane and present the 0.16 nm spatial imaging resolution based on this suspended thin membrane geometric construction, which is characterized by scanning transmission electron microscope (STEM). The suspended membrane serves as an energy filter of helium ion beam and due to the elimination of backscattering induced secondary electrons, we can systematically study the factors that influences the LER of the fabricated nanostructures. Furthermore, we explore the parameters including step size, designed exposure linewidth (DEL), delivered dosage and resist thickness and choosing the high contrast developer, the process window allows to fabricate lines with 0.2nm LER is determined. AFM measurement and simulation work further reveal that at specific beam step size and DEL, the nanostructures with minimum LER can only be fabricated at specific resist thickness and dosage. .
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In microfluidic systems, it is important to maintain flow stability to execute various functions, such as chemical reactions, cell transportation, and liquid injection. However, traditional flow sources, often bulky and prone to unpredictable fluctuations, limit the portability and broader application of these systems. Existing fluidic stabilizers, typically designed for specific flow sources, lack reconfigurability and adaptability in terms of the stabilization ratios. To address these limitations, a modular and standardized stabilizer system with tunable stabilization ratios is required. In this work, we present a Lego-like modular microfluidic stabilizer system, which is fabricated using 3D printing and offers multi-level stabilization combinations and customizable stabilization ratios through the control of fluidic RC constants, making it adaptable to various microfluidic systems. A simplified three-element circuit model is used to characterize the system by straightforwardly extracting the RC constant without intricate calculations of the fluidic resistance and capacitance. By utilizing a simplified three-element model, the stabilizer yields two well-fitted operational curves, demonstrating an R-square of 0.95, and provides an optimal stabilization ratio below 1%. To evaluate the system's effectiveness, unstable input flow at different working frequencies is stabilized, and droplet generation experiments are conducted and discussed. The results show that the microfluidic stabilizer system significantly reduces flow fluctuations and enhances droplet uniformity. This system provides a new avenue for microfluidic stabilization with a tunable stabilization ratio, and its plug-and-play design can be effectively applied across diverse applications to finely tune fluid flow behaviors in microfluidic devices.
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Stretchable electronics commonly assemble multiple material modules with varied bulk moduli and surface chemistry on one packaging substrate. Preventing the strain-induced delamination between the module and the substrate has been a critical challenge. Here we develop a packaging substrate that delivers mechanically stable module/substrate interfaces for a broad range of stiff and stretchable modules with varied surface chemistries. The key design of the substrate was to introduce module-specific stretchability and universal adhesiveness by regionally tuning the bulk molecular mobility and surface molecular polarity of a near-hermetic elastic polymer matrix. The packaging substrate can customize the deformation of different modules while avoiding delamination upon stretching up to 600%. Based on this substrate, we fabricated a fully stretchable bioelectronic device that can serve as a respiration sensor or an electric generator with an in vivo lifetime of 10 weeks. This substrate could be a versatile platform for device assembly.
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In order to study the effect of the venting direction on explosion pressure in liquefied petroleum gas pipelines, explosion accident scenarios are experimentally tested and numerically simulated in a pipeline model with different explosion venting directions. In addition, the effect characteristic is analyzed through the pressure field varying with time and peak pressure varying with the distance. Results show that the pressure in the vertical branch decreases sharply, while the pressure in the horizontal branch does not show an obvious decrease with explosion venting of the vertical branch. However, the pressure decreases obviously in both branches with explosion venting of the horizontal branch, and the biggest reduction of peak pressure of monitoring points is 73.55% compared with that without venting. In addition, large areas of negative pressure appear in both branches with explosion venting of the vertical branch; however, a large area of negative pressure area appears in the horizontal branch with explosion venting of the horizontal branch. What is more, the arrival time of peak pressure in the main pipe of the explosion pipeline is significantly reduced with explosion venting, which is caused by the different generation ways of peak pressure. The effect analysis result of the venting direction on explosion pressure could aid the optimal layout design of LPG pipelines with the location of venting and important facilities as well as with the selection of negative-pressure-resistant material and higher-accuracy sensors.
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Fully biodegradable packaging materials are demanded to resolve the issue of plastic pollution. However, the fresh food storage performance of biodegradable materials is generally much lower than that of plastics due to their high permeability, microbial friendliness, and limited stretchability and transparency. Here a biodegradable packaging material is reported with high fresh food storage performance based on an oil-infused bacterial cellulose (OBC) porous film. The oil infusion significantly improved cellulose's food-keeping performance by reducing its gas permeability, increasing its stretchability and transparency, and enabling the active release of green vapor-phase preservative molecules, while maintaining its intrinsically high degradability. Strawberries stored in a container with the OBC lid at 23 °C after 5 days exhibited a moldy rate of 0%, in contrast to the 100% moldy rate of those stored by poly(ethylene). Enhanced storage performance is also obtained on tomatoes, pork, and shrimp. The OBC film is naturally degraded after being buried in wet soil at 30 °C for 9 days, identical to the degradation rate of bacterial cellulose. The liquid seal strategy broadly applies to different celluloses, providing a general option for developing cellulose-based biodegradable packaging materials.
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Celulose , Embalagem de Alimentos , Armazenamento de Alimentos , Embalagem de Alimentos/métodos , Celulose/metabolismo , Celulose/química , Armazenamento de Alimentos/métodos , Permeabilidade , Bactérias/metabolismo , Biodegradação AmbientalRESUMO
The residues of pesticides and antibiotics have always been a major concern in agriculture and food safety. In order to provide a new method for the rapid detection of organophosphorus pesticides and antibiotics, a novel Cd(II) chain-based zwitterionic metal-organic framework MOF 1 with high sensitivity fluorescence sensing performance was successfully synthesized. A series of researches showed that the water- and pH-stable bifunctional MOF 1 has a great ability to detect phosmet (PSM) and chlortetracycline (CTC) in water through fluorescence quenching effect, with high detection sensitivity, low detection limits (0.0124 µM and 0.0131 µM), short response time (40 s) and reusability. Practical application results revealed that MOF 1 could detect PSM and CTC in milk, beef, chicken and egg samples, with satisfactory recoveries (95.2%-103.7%). As a novel fluorescence probe, MOF 1, is known the first case that can detect PSM in animal-derived samples, and the first dual-function material capable of detecting PSM and CTC. Mechanism studies displayed that competitive absorption and photoinduced electron transfer clearly authenticate the high quenching performance of the material.
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Clortetraciclina , Estruturas Metalorgânicas , Praguicidas , Fosmet , Animais , Bovinos , Estruturas Metalorgânicas/química , Cádmio , Água , Compostos Organofosforados , Antibacterianos/análiseRESUMO
Images are one of the important sources of getting information, and the process of getting images can be affected by various factors. Atmospheric turbulence is one of them. Ghost imaging has a positive effect on suppressing atmospheric turbulence, but its reconstruction results are not stable, and it cannot get high-quality images under extreme conditions. In this paper, we simulate atmospheric turbulence using a phase screen, combine computational ghost imaging to simulate the imaging process, and analyze the factors that affect the imaging. We use an end-to-end neural network to input the bucket signal into the network after processing, which can not only reconstruct the target image directly but also save reconstruction time by removing the process of correlation calculation. Simulations show that good reconstruction results can be obtained at low sampling rates and extreme conditions.
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OBJECTIVE: To investigate the clinical value of laparoscopic cytoreductive surgery (CRS) in treating of appendiceal pseudomyxoma peritonei with limited disease and low tumor burden. METHODS: The clinical data of patients with appendiceal pseudomyxoma peritonei treated by surgery with CRS at the Aerospace Center Hospital from January 2018 to December 2021 were retrospectively analyzed. The patients were divided into laparoscopic or open CRS groups according to the operation method. A propensity score-matched (PSM) analysis (1:1) was performed, the related clinical variables were compared between the two groups, and the effect on progression-free survival (PFS) was also analyzed. RESULTS: One hundred and eight patients were included in this study. After PSM, 33 patients were selected from each group and the age and peritoneal cancer index were matched between the two groups. There were significant differences in operation time (P < 0.001), intraoperative bleeding (P < 0.001), intraoperative blood transfusion (P = 0.007), hospital stay (P < 0.001). The analysis of PFS showed that there was no significant difference between the two operation methods. After multivariate analysis, the pathologic subtype (P = 0.012) was identified as an independent prognostic factor for PFS. CONCLUSION: The curative effect of laparoscopic CRS is like that of open operation, which can significantly shorten the operation time and hospital stay and reduce intraoperative bleeding and blood transfusion event. The laparoscopic CRS is safe and feasible in strictly selected patients. The pathologic subtype is an independent factor affecting the prognosis for PFS.
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Hipertermia Induzida , Laparoscopia , Neoplasias Peritoneais , Pseudomixoma Peritoneal , Humanos , Pseudomixoma Peritoneal/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos de Citorredução/métodos , Carga Tumoral , Hipertermia Induzida/métodos , Terapia Combinada , Taxa de SobrevidaRESUMO
Angiogenesis is required for tumor progression; thus, its investigation can be useful to identify strategies for potential cancer treatments. Tripartite motif 47 (TRIM47) is involved in the progression of multiple cancers. However, its role in glioma angiogenesis is largely unknown. In this study, we first showed that TRIM47 is frequently upregulated in gliomas, and increased TRIM47 levels are correlated with microvascular density. We then examined the role of TRIM47 in cellular functions related to angiogenesis in vitro and observed that TRIM47 knockdown significantly reduced human umbilical vein endothelial cell proliferation, migration, and tube formation. We also found that TRIM47 silencing reduced vessel density and tumor volume in glioma xenografts. Mechanistically, TRIM47 negatively regulated Smad4 expression in glioma cells, and SMAD4 knockdown rescued the suppressive effects of TRIM47 silencing. Taken together, our results indicate that TRIM47 promotes angiogenesis in gliomas by downregulating SMAD4. Therefore, targeting the TRIM47/SMAD4 axis may offer an innovative approach to glioma treatment.
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Glioma , Humanos , Animais , Glioma/genética , Glioma/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteína Smad4/genética , Proteína Smad4/metabolismo , Proteínas de Transporte/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genéticaRESUMO
Background: Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has become an increasingly vital tool for modifying gene expression in a variety of cell types. Lentiviral transduction and electroporation are the two main approaches used to deliver CRISPR/Cas9 into cells. However, the application of CRISPR/Cas9 in primary hematopoietic cells has been limited due to either low transduction efficiency in terms of viral-based delivery or difficult selection and enrichment of transfected and edited cells with respect to electroporation of CRISPR/Cas9 ribonucleoprotein (RNP). Methods: In this study in vitro transcription was used to synthesize the guide RNA (gRNA), and plasmid pL-CRISPR.EFS.GFP was used as its DNA template. Then the in vitro transcribed gRNA was labeled with pCp-Cy5 via T4 ligase before incubating with Cas9 protein. Furthermore, CRISPR/Cas9 RNP was electroporated into primary CD34+ cells isolated from cord blood, and cell survival rate and transfection efficiency were calculated and compared to that of lentiviral transduction. Results: Here, we show that electroporation of CRISPR/Cas9 RNP resulted in higher cell viability compared to electroporation of CRISPR/Cas9 all-in-one plasmid, providing important findings for further studies in hematology via CRISPR/Cas9 technology. Moreover, we established a method for labeling in vitro-transcribed gRNA with fluorophore and the sorted fluorescent cells displayed higher knockout efficiency than nonsorted transfected cells. Conclusions: Electroporation of fluorescence labeled CRISPR/Cas9 RNP is a perspective approach of gene editing. Our study provides an efficient and time-saving approach for genome-editing in hematopoietic cells.
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A novel cationic iridium(III) complex [(ppy)2Ir(bPCPC)]PF6 (ppy: 2-phenylpyridine; bPCPC: 2-([2,2'-bipyridine]-4-carbonyl)-N-phenylhydrazinecarbothioamide) containing a thiosemicarbazide unit was designed and synthesized. The thiosemicarbazide unit was a sensitive functional group to Hg2+, when it reacted with Hg2+, it was desulphurized and thus led to the formation of 1,3,4-oxadiazole, [(ppy)2Ir(bPCPC)]PF6 resultantly was used as a "turn-on" chemodosimeter for luminescent detection of Hg2+ in DMF/PBS buffer solution at pH = 7-11. Except for Ag+, recognition capability of [(ppy)2Ir(bPCPC)]PF6 to Hg2+ was not interfered by other common metal ions (Co2+, Li+, Zn2+, Pb2+, K+, Al3+, Na+, Mn2+, Cu2+, Fe2+, Fe3+, Cr3+, Ba2+, Mg2+, Ni2+ and Ca2+). The detection limit was 1.83 × 10-9 molâL-1 (0.37 ppb), which indicated the complex was a highly sensitive chemiluminescent detection reagent of Hg2+.
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Irídio , Mercúrio , Cátions , SemicarbazidasRESUMO
Cracking con-rod is an advanced high-precision connecting structure based on brittle expansion, breaking and reconnection of steel, to solve the problem of assembly circle missing. High carbon micro-alloyed steel C70S6, as a dominant material for the production of cracking con-rod, has extremely strict requirements on non-metallic inclusions in steel and microstructure stability. Continuous casting tundish plays an important role in removing large-sized inclusions and stabilizing casting quality. Aiming at the inconsistent casting quality of C70S6 steel produced by a three-strand asymmetric tundish and the frequent occurrence of slag entrapment problems in Xining Special Steel, the tundish structure was optimized by means of physical modelling combined with numerical simulation, and the quality of the bloom castings and subsequent hot-rolled products before and after optimization were compared based on volume production. The results show that a new flow control design to the tundish can effectively improve the consistency of its metallurgical effect for each of the three strands and the following overall product quality, in which the flow field and temperature field in the tundish are more uniform. This is due to the adoption of a vortex inhibitor and an optimized wall structure according to the measured RTD curve, ink trajectory and numerical simulation on the 3-D streamline contours and temperature distribution in the tundish. The peak concentration of outlet 1 is decreased from 6.5 before optimization to less than 2.0 after optimization, which means the elimination or alleviation of the local short-circuit flow. The maximum temperature difference of C70S6 molten steel measured at the outlets of the tundish three strands is decreased from 2-5 °C to 1-3 °C, which is in good agreement with the numerical simulation results. The difference in columnar crystal ratio of the corresponding bloom castings is decreased from 2.27-3.17% to 1.26-1.85%, and the consistency of central carbon segregation index is also significantly improved. In addition, the difference in oxygen content among the three strand blooms is decreased from 1.7-3.5 ppm to 0.8-1.9 ppm. As a result, the overall mechanical properties and microstructure stability of the hot-rolled products are improved statistically, in which the hardness fluctuation is decreased from 84 HBW to 60 HBW, the inclusion grade of types B + C + D + Ds is reduced to 1.105, and the occurrence rate of Ds dropped to 0.118%. Accordingly, the failure rate of the cracking con-rod is controlled stably within 4‱, and the fracture is generally smoother than that before tundish optimization. In summary, the flow field optimization to a multi-strand asymmetric tundish has a clear effect on improving the overall quality of its bloom castings and rolled products, which should be paid more attention industrially. Meanwhile, the present study provides a reliable theoretical and experimental reference for the improvement of metallurgical effects of an asymmetric-typed tundish commonly used in special steel production.
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Bacteriophage T7 gene 17.5 coding for the only known holin is one of the components of its lysis system, but the holin activity in T7 is more complex than a single gene, and evidence points to the existence of additional T7 genes with holin activity. In this study, a T7 phage with a gene 17.5 deletion (T7-â³holin) was rescued and its biological characteristics and effect on cell lysis were determined. Furthermore, the genomic evolution of mutant phage T7-â³holin during serial passage was assessed by whole-genome sequencing analysis. It was observed that deletion of gene 17.5 from phage T7 delays lysis time and enlarges the phage burst size; however, this biological characteristic recovered to normal lysis levels during serial passage. Scanning electron microscopy showed that the two opposite ends of E. coli BL21 cells swell post-T7-â³holin infection rather than drilling holes on cell membrane when compared with T7 wild-type infection. No visible progeny phage particle accumulation was observed inside the E. coli BL21 cells by transmission electron microscopy. Following serial passage of T7-â³holin from the 1st to 20th generations, the mRNA levels of gene 3.5 and gene 19.5 were upregulated and several mutation sites were discovered, especially two missense mutations in gene 19.5, which indicate a potential contribution to the evolution of the T7-â³holin. Although the burst size of T7-â³holin increased, high titer cultivation of T7-â³holin was not achieved by optimizing the culture process. Accordingly, these results suggest that gene 19.5 is a potential lysis-related component that needs to be studied further and that the T7-â³holin strain with its gene 17.5 deletion is not adequate to establish the high-titer phage cultivation process.
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BACKGROUND: At present, the process of inspection and quarantine starts with sampling at the customs port, continues with transporting the samples to the central laboratory for inspection experiments, and ends with the inspected results being fed back to the port. This process had the risks of degradation of biological samples and generation of pathogenic microorganisms and did not meet the rapid on-site detection demand because it took a rather long time. Therefore, it is urgently needed to develop a rapid and high-throughput detection assay of pathogenic microorganisms at the customs port. The aim of this study was to develop a microfluidic chip to rapidly detect swine pathogenic microorganisms with high-throughput and higher accuracy. Moreover, this chip will decrease the risk of spreading infection during transportation. RESULTS: A series of experiments were performed to establish a microfluidic chip. The resulting data showed that the positive nucleic acid of four swine viruses were detected by using a portable and rapid microfluidic PCR system, which could achieve a on-site real-time quantitative PCR detection. Furthermore, the detection results of eight clinical samples were obtained within an hour. The lowest concentration that amplified of this microfluidic PCR detection system was as low as 1 copies/µL. The results showed that the high specificity of this chip system in disease detection played an important role in customs inspection and quarantine during customs clearance. CONCLUSION: The microfluidic PCR detection system established in this study could meet the requirement for rapid detection of samples at the customs port. This chip could avoid the risky process of transporting the samples from the sampling site to the testing lab, and drastically reduce the inspection cycle. Moreover, it would enable parallel inspections on one chip, which greatly raised the efficiency of inspection.
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Dispositivos Lab-On-A-Chip/veterinária , Reação em Cadeia da Polimerase Multiplex/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Suínos/virologia , Animais , Circovirus/genética , Circovirus/isolamento & purificação , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/isolamento & purificação , Ensaios de Triagem em Larga Escala , Dispositivos Lab-On-A-Chip/virologia , Microfluídica/instrumentação , Reação em Cadeia da Polimerase Multiplex/métodos , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Suínos , Doenças dos Suínos/diagnósticoRESUMO
In this study, hierarchical Ni-Co-Mn hydroxide hollow architectures were successfully achieved via an etching process. We first performed the synthesis of NiCoMn-glycerate solid spheres via a solvothermal route, and then NiCoMn-glycerate as the template was etched to convert into hierarchical Ni-Co-Mn hydroxide hollow architectures in the mixed solvents of water and 1-methyl-2-pyrrolidone. Hollow architectures and high surface area enabled Ni-Co-Mn hydroxide to manifest a specific capacitance of 1626 F g-1 at 3.0 A g-1, and it remained as large as 1380 F g-1 even at 3.0 A g-1. The Ni-Co-Mn hydroxide electrodes also displayed notable cycle performance with a decline of 1.6% over 5000 cycles at 12 A g-1. Moreover, an asymmetric supercapacitor assembled with this electrode exhibited an energy density of 44.4 W h kg-1 at 1650 W kg-1 and 28.5 W h kg-1 at 12 374 W kg-1. These attractive results demonstrate that hierarchical Ni-Co-Mn hydroxide hollow architectures have broad application prospects in supercapacitors.
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A novel advanced oxidation process (AOP) using ultraviolet/sodium chlorite (UV/NaClO2) is developed for simultaneous removal of SO2 and NO. NH4OH, as an additive, was used to inhibit the generation of ClO2 and NO2. The removal efficiencies of SO2 and NO reached 98.7 and 99.1%. NO removal was enhanced by greater UV light intensity and shorter wavelengths but was insensitive to changes in pH and temperature. SO2 at 500-1000 mg/m3 improved NO removal, especially in the absence of UV. The coexistence of SO2 and O2 facilitated the removal of NO by ClO2-. HCO3-, Cl-, and Br- enhanced NO removal, but their roles were negligible when UV was added. The generation of ClO2 and ClOâ¢/HO⢠was verified by an UV-vis spectrometer, electron spin resonance (ESR), and radical-quenching tests. The mechanisms responsible for the removal of SO2 and NO were attributed to the synergism between acid-base neutralization and radical-induced oxidation. The ClO2- evolution and product composition were demonstrated by UV-vis and X-ray photoelectron spectroscopy (XPS). Kinetics analyses showed that the Hatta numbers were 329-798 and 747-1000 without and with UV. Thus, the gas-film resistance mainly controlled the mass-transfer process.
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Amônia , Cloretos , Oxirredução , Raios UltravioletaRESUMO
A novel orange-yellow-emitting polymethyl methacrylate derivative grafted with cationic iridium(III) complex units was synthesized and used as down-conversion luminescent materials in light-emitting diodes (LEDs). The polymer had a thermal decomposition temperature (Td) of 275 °C. With the temperature increasing from 20 to 100 °C, its photoluminescent intensity decreased to 76.8% with thermal quenching activation energy (Ea) of 0.2775 eV. A series of LEDs was fabricated by 460 nm blue GaN chips and the polymer blended in silicone at different concentrations. At 4.0 wt %, a cold white LED was obtained, the correlated color temperature (CCT) was 10,050 K, color rendering index (CRI) was 71.2, luminous efficiency (ηL) was 5.3 lm·w-1, and Commission Internationale de L'Eclairage (CIE) chromaticity coordinates were (0.30, 0.24). At 5.0 wt.%, the LED emitted neutral white light, its CCT was 4938 K, CRI was 75, ηL was 13.8 lm·w-1, and the CIE value was (0.34, 0.27). At 5.5 wt %, 6.0 wt %, 7.0 wt %, and 8.0 wt %, the LEDs all emitted warm white light; their CCTs were 3446, 3093, 2557, and 2337 K, respectively; their CRIs were 73.6, 71.8, 63.8, and 59.0, respectively; their ηL were 18.1, 16.3, 14.8, and 13.7 lm·w-1, respectively; and their CIE values were (0.36, 0.30), (0.40, 0.35), (0.45, 0.38), and (0.50, 0.42), respectively. At 9.0 wt %, the blue light of GaN chip was completely absorbed by the polymer and only the orange-yellow light of the polymer emitted. The results suggested the polymer was a promising orange-yellow-emitting phosphor candidate for white LEDs, especially for warm white LEDs.
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The reported metal-organic framework (MOF) catalyst realizes CO2 to methanol transformation under ambient conditions. The MOF is one rare example containing metal-free N-heterocyclic carbene (NHC) moieties, which are installed using an in situ generation strategy involving the incorporation of an imidazolium bromide based linker into the MOF by postsynthetic ligand exchange. Importantly, the resultant NHC-functionalized MOF is the first catalyst capable of performing quantitative hydrogen transfer from silanes to CO2 , thus achieving quantitative (>99 %) methanol yield. Density-functional theory calculations indicate the high catalytic activity of the NHC sites in MOFs are attributed to the decreased reaction barrier of a reaction route involving the formation of an NHC-silane adduct. In addition, the MOF-immobilized NHC catalyst shows enhanced stability for up to eight cycles without base activation, as well as high selectivity towards the desired silyl methoxide product.
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Ultrafast time-stretch imaging technique recently attracts an increasing interest for applications in cell classification due to high throughput and high sensitivity. A novel imaging modality of time-stretch imaging technique for edge detection is proposed. Edge detection based on the directional derivative is realized using differential detection. As the image processing is mainly implemented in the physical layer, the computation complexity of edge extraction is significantly reduced. An imaging system for edge detection with the scan rate of 77.76 MHz is experimentally demonstrated. Resolution target is first measured to verify the feasibility of the edge extraction. Furthermore, various cells, including red blood cells, lung cancer cells and breast cancer cells, are detected. The edges of cancerous cells present in a completely different form. The imaging system for edge detection would be a good candidate for high-throughput cell classification.