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The applicability of whispering gallery mode (WGM) microsphere resonators is limited due to the intricate modes and dense spectrum they exhibit. This article investigates the spectral cleaning approach of WGM microsphere resonators through simulation and experiments. Additionally, a method is proposed to suppress the excitation of higher-order azimuthal modes in WGM microsphere resonators by etching double-grooved micro-nanostructures on the surface of the microspheres. This approach achieves resonance mode selection and spectral cleaning, and leads to an enhancement of the extinction ratio of resonance peaks (from 1.068 dB to 1.8 dB, representing an improvement of approximately 0.732 dB). Consequently, this advancement establishes the necessary conditions for achieving long-range tracking of a single resonance peak. Meanwhile, a double T-grooved structure has been proposed based on the mode distribution characteristics of the spherical microcavity. Experimental results indicate a significant enhancement in the quality factor (Q-value) of the microsphere cavity, with an improvement of one order of magnitude (from ∼104 to ∼105) observed following the etching process, as compared to the double rectangular grooves configuration. The process presented in this research article demonstrates an efficient approach to suppressing the excitation of higher-order azimuthal modes in microsphere resonators. This method achieves resonance mode selection and simplifies the spectra, addressing the challenge of applying mode densities in large-sized spherical microcavities.

To reduce the loss of the high-frequency drive circuit of silicon carbide metal oxide semiconductor transistor (SiC MOSFET) and to better utilize the performance of the SiC MOSFET, a high-frequency drive circuit based on discrete components (DC-RGD) is proposed in this paper. The inductance is added to provide a low-impedance circuit for the gate charge/discharge circuit of the SiC MOSFET, enhancing the circuit’s immunity to interference. At the same time, an auxiliary switching tube is added to form an active clamping circuit to reduce the impact of parasitic parameters on the drive waveform in high-frequency applications. A negative voltage is generated by adding a series capacitor to the drive circuit, ensuring the auxiliary switch is on during SiC MOSFET turn-off. This switch is not driven by an additional drive circuit, thus simplifying the circuit. The operation and losses of the circuit are analyzed, and the design methodology of the circuit is given. Finally, a Boost converter with an input of 24 V and an output of 48 V/5 A is constructed. The operating waveforms at a frequency of 0.5 MHz are tested, and the loss of the driving circuit is only 0.317 W. The results show that the proposed driving circuit ensures the reliability of the SiC MOSFETs and is able to solve the problem of the driving waveform oscillations efficiently, with a better anti-interference capability and lower loss.

The production of nitrogen-doped carbon quantum dots (N-CDs) from walnut shell waste is crucially important for green chemistry and sustainable development. Herein we fabricate N-CDs by a bottom-up solvothermal method and use the novel N-CDs to modify the electron transport layer (ETL) in perovskite solar cells (PVSCs). The N-CDs can produce 440 nm fluorescence under the excitation of 350 nm light with a quantum yield of 8.75%. Infrared absorption spectra show that N-CDs contain high proportions of nitrogen-containing and oxygen-containing functional groups. , Through the incorporation of N-CDs into SnO2 ETL, the formation of defects is inhibited, and crystallinity is improved. This is because the N-CDs contains a large number of functional groups such as nitrogen and oxygen and these groups would interact with the ETL and perovskite, which reduce the defect/trap centers in PVSCs. Therefore, the N-CDs modified PVSCs show improved power conversion efficiency. This study provides a novel way to use walnut shell waste to synthesize N-CDs and achieve efficient and stable perovskites solar cells.

An increase in photosynthetic efficiency can increase the production of fruits and vegetables. Due to many limitations, plants generally use much less photosynthetic capacity because they do not absorb all incoming sunlight. Plant nano-bionics investigates Carbon quantum dots (CDs) having the high light-harvesting capability, which could be used to improve the photosynthesis efficiency of plants. To increase the yield of cucumber, this paper studied the effects of different concentrations of CDs on the growth of cucumber seedlings. We synthesized and tested nontoxic dual-emissive CDs for the photosynthetic efficiency increase in cucumber seedlings. We found that the concentration of CDs (1500 mg/l) achieves the best growth promotion of cucumber seedlings. The contents of flavonoids, soluble sugars, carotenoids, and total chlorophyll in the treated cucumber seedlings increased by 19.90%, 26.78%, 117.77%, 81.65%, respectively. Meanwhile, we found that the leaf area, net photosynthetic rate, photosynthetic pigments, and photosynthetic parameters of cucumber seedlings were improved to a certain extent after treatment with an appropriate concentration of CDs. In summary, carbon quantum dots have strong application prospects in cucumber production.

OBJECTIVE--The role of NOX2-containing NADPH oxidase in the development of diabetes is not fully understood. We hypothesized that NOX2 deficiency decreases reactive oxygen species (ROS) production and immune response and protects against streptozotocin (STZ)-induced β-cell destruction and development of diabetes in mice. RESEARCH DESIGN AND METHODS--Five groups of mice--wild-type (WT), [NOX2.sup.-/-], WT treated with apocynin, and WT adoptively transferred with [NOX2.sup.-/-] or WT splenocytes--were treated with multiple-low-dose STZ. Blood glucose and insulin levels were monitored, and an intraperitoneal glucose tolerance test was performed. Isolated WT and [NOX2.sup.-/-] pancreatic islets were treated with cytokines for 48 h. RESULTS--Significantly lower blood glucose levels, higher insulin levels, and better glucose tolerance was observed in [NOX2.sup.-/-] mice and in WT mice adoptively transferred with [NOX2.sup.-/-] splenocytes compared with the respective control groups after STZ treatment. Compared with WT, β-cell apoptosis, as determined by TUNEL staining, and insulitis were significantly decreased, whereas β-cell mass was significantly increased in [NOX2.sup.-/-] mice. In response to cytokine stimulation, ROS production was significantly decreased, and insulin secretion was preserved in [NOX2.sup.-/-] compared with WT islets. Furthermore, proinflammatory cytokine release induced by concanavalin A was significantly decreased in [NOX2.sup.-/-] compared with WT splenocytes. CONCLUSIONS--NOX2 deficiency decreases β-cell destruction and preserves islet function in STZ-induced diabetes by reducing ROS production, immune response, and β-cell apoptosis. Diabetes 59:2603-2611, 2010, Type 1 diabetes is a T-cell-mediated autoimmune disease characterized by the selective destruction of insulin-secreting β-cells in the islets of Langerhans. It is a multifactorial process involving autoantigen presentation by [...]

Bats (Chiroptera), the second largest group of mammals, are known for their unique immune system and their ability to act as vectors for various zoonoses. Bats also act as important carriers of fungi, which include plant, animal, and human pathogens. Their roosting areas, foraging behaviors, and even migration routes make bats ideal vectors for fungi. We isolated 75 culturable fungal species from bats in Yunnan Province, China, with 36 species representing known pathogens of plants, animals, and humans, while 39 species are non-pathogenic fungi. Among these species, 77% (58 species) belonged to Ascomycota, 9% (seven species) belonged to Basidiomycota, and 13% (10 species) belonged to Mucoromycota. Even though several taxonomic studies on fungi associated with bats have been published, studies exploring the role of bats as fungal vectors are lacking. This study discusses the fungi host-specific traits and pathogenicity and the impact and ecological significance of bats as fungal vectors.

Combinatorial cancer therapies based on nanomedicine have emerged as a promising strategy to achieve potentiated treatment efficiency. Herein, cisplatin (CDDP) prodrug (Pt-CD) and a mitochondria-targeted near-infrared (NIR) photosensitizer IR780 were combined to construct a multifunctional nanomedicine IR780@Pt NPs through a supramolecular self-assembly strategy. Targeted mitochondrial dysfunction of cancer cells was sufficiently induced under NIR laser irradiation through both photothermal and photodynamic effects, inhibiting the overactive mitochondrial energy pathways of cancer cells. The mitochondrial dysfunction significantly attenuated the crosstalk between mitochondria and nucleus viathe cellular ATP energy chain, leading to obvious down-regulation of the key proteins of the nucleotide excision repair (NER) pathway. Thereby, the chemotherapeutic effect of CDDP could be significantly potentiated because of reduced DNA lesion repair capacity by ERCC1-XPF nuclease system. Moreover, IR780@Pt NPs exhibited excellent NIR fluorescence and photoacoustic (PA) imaging capacity for in vivoimaging-guided NIR laser treatment. Ultimately, the IR780@Pt NPs mediated combinatorial chemophototherapy achieved potentiated anticancer efficacy against cancer cells in vitroand tumor inhibition performance in vivo. Overall, this study highlighted the significance of nanomedicine mediated targeted induction of mitochondrial dysfunction to potentiate chemotherapy for efficient combinatorial cancer therapy.

Two new sets of UiO-Zr metal–organic framework (MOF) bearing mixed linkers BDC-(SCH3)2and BDC-(SOCH3)2that have different band gaps and edges were prepared through post oxidation and direct methods, namely, UiO-66-(SCH3)2-xh(x= 4, 9, 12 oxidation hours) and UiO-66-(SOCH3)x(SCH3)2–x(x= 0, 0.4, 0.6, 2), respectively. These composites with stoichiometric components were fully characterized via proton nuclear magnetic resonance (1H NMR) spectroscopy, powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectra, Brunauer–Emmett–Teller (BET), photo electrochemical measurements, and femtosecond transient absorption (fs-TA) spectroscopy. The structure, electronic property, and photoresponsive and catalytic ability as the functions of the molar ratio of linkers and the synthetic protocol were first investigated. The mixed-linker UiO-66-(SCH3)2-xhand UiO-66-(SOCH3)x(SCH3)2–xexhibited improved performances as compared to the UiO-66-(SCH3)2and UiO-66-(SOCH3)2possessing neat linkers only. Their photo response and catalytic activity varied with different linker ratios. For UiO-66-(SCH3)2-xh, the performance increased with the increasing linker BDC-(SOCH3)2ratio upon oxidation but reached the highest as the BDC-(SOCH3)2being of 24.4% in UiO-66-(SCH3)2-9h. In comparison, the best photocurrent (80.74 uA/cm–2) and the highest H2generation rate (2018.8 μmol g–1h–1) (λ > 400 nm) in UiO-66-(SCH3)2-9hare about twice those of UiO-66-(SOCH3)0.4(SCH3)1.6obtained by direct synthesis, although the linker BDC-(SOCH3)2ratio of those two composites is almost the same (24.4% vs 23.9%). Recorded shorter lifetime and higher charge separation efficiency of the former than those of the latter suggest the postsynthetic protocol as the efficient method for achieving the mixed-liner-MOF-based photocatalyst with high performance. A new type-II tailored homojunction is proposed in these mixed-linker MOFs for their efficient charge separation and improved activity.

A new wood-inhabiting fungal species,Phlebiopsis yunnanensissp. nov., is proposed based on morphological and molecular characters. The species is characterized by resupinate, membranaceous to subceraceous basidiocarps, a monomitic hyphal system with simple separated generative hyphae, cystidia conical, thick-walled, heavily encrusted with large crystals in the apical part and ellipsoid basidiospores measuring 3.5–4.5×2.5–3.5 μm. The internal transcribed spacer (ITS) and the large subunit (LSU) regions of nuclear ribosomal RNA gene sequences of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and bayesian inference methods. The phylogenetic analyses based on molecular data of ITS+nLSU sequences showed thatP. yunnanensisbelonged to the Phanerochaetaceae and nested into the phlebioid clade. Further investigation was obtained for more representative taxa in thePhlebiopsisbased on ITS+nLSU sequences, in which the result demonstrated that the speciesP. yunnanensisformed a monophyletic lineage with a strong support (100% BS, 100% BP, 1.00 BPP) and then grouped withP. gigantea andP. lamprocystidiata.

NiMoB alloy films were deposited on silicon substrate by electroless deposition for diffusion barrier application in copper interconnects technology. NiMoB(40nm)/SiO2/Si and NiMoB(20nm)/Cu (40nm)/NiMoB(40nm)/SiO2/Si samples were prepared and annealed at temperatures ranging from 400◦C to 600◦C. Samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Four Point Probes (FPP) and Atomic Force Microscopy (AFM) to investigate the phases, composition, sheet resistance and surface morphology. The results showed that electroless deposited NiMoB film can be used as an effective Cu diffusion barrier layer until 500◦C. And the failure mechanism is that NiMoB crystallized and grains grew after annealing at high temperature, a large number of Cu grains passed through NiMoB film via grain boundaries and then reacted with Si substrate and oxygen, causing the generation of highly resistive Cu4Si and CuO.

This study focuses on the development of the pervoskite catalyst for aluminum-air battery. The catalyst powders of porous pervoskite LaMnO3 were prepared by template method with different calcination temperatures. Material characteristics of prepared samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermalgravimetry (TG). The half-cell polarization curves and cyclic voltammetry curves were found to be strongly depended on the calcination temperature. The result showed the optimized calcination temperature was 650°C. The full-cell discharge test in NaCl solution (3.5 wt%) with a constant discharge current of 10 mA/cm2 was performed at room temperature, and the discharge voltage of sample synthesized under optimized calcination temperature was 0.73 V.

In this work, graphene quantum dots were simply and rapidly prepared by thermal decomposition of citric acid. The resulting graphene quantum dots shows good dispersion and high crystallinity, the sizes can be effectively adjusted by controlling the temperature of decomposition. The results indicate that with the increase of temperature, the size of GQDs increased from 2 nm to 12 nm. The effect of the size of graphene quantum dots on the optical properties were carefully studied. Based on the optical properties and electrochemical results, the HOMO and LUMO value of GQDs with different sizes were obtained and the band gap becomes smaller from 3.36 eV to 2.87 eV with the increase of size of GQDs, which provides a potential application in the field of optoelectronic devices.

Momordica charantiaL., a vegetable crop with high nutritional value, has been used as an antimutagenic, antihelminthic, anticancer, antifertility, and antidiabetic agent in traditional folk medicine. In this study, the antifungal activity of M. charantiaseed extract toward Fusarium solaniL. was evaluated. Results showed that M. charantiaseed extract effectively inhibited the mycelial growth of F. solani, with a 50% inhibitory rate (IC50) value of 108.934 μg/mL. Further analysis with optical microscopy and fluorescence microscopy revealed that the seed extract led to deformation of cells with irregular budding, loss of integrity of cell wall, as well as disruption of the fungal cell membrane. In addition, genomic DNA was also severely affected, as small DNA fragments shorter than 50 bp appeared on agarose gel. These findings implied that M. charantiaseed extract containing α-momorcharin, a typical ribosome-inactivating protein, could be an effective agent in the control of fungal pathogens, and such natural products would represent a sustainable alternative to the use of synthetic fungicides.

Ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is the key enzyme to assimilate CO2into the biosphere. The nonredundant structural data sets for three RuBisCO domain superfamilies, i.e. large subunit C-terminal domain (LSC), large subunit N-terminal domain (LSN) and small subunit domain (SS), were selected using QRfactorization based on the structural alignment with QHas the similarity measure. The structural phylogenies were then constructed to investigate a possible functional significance of the evolutionary diversification. The LSC could have occurred in both bacteria and archaea, and has evolved towards increased complexity in both bacteria and eukaryotes with a 4-helix–2-helix–2-helix bundle being extended into a 5-helix–3-helix–3-helix one at the LSC carboxyl-terminus. The structural variations of LSN could have originated not only in bacteria with a short coil, but also in eukaryotes with a long one. Meanwhile, the SS dendrogram can be contributed to the structural variations at the βA–βB-loop region. All the structural variations observed in the coil regions have influence on catalytic performance or CO2/O2selectivities of RuBisCOs from different species. Such findings provide insights on RuBisCO improvements.

CoMoB film was prepared on Si substrate via electroless deposition as the diffusion barrier for ULSI-Cu metallization. Annealing experiments of CoMoB(30nm) film and CoMoB(10nm)/Cu (40nm)/CoMoB(30nm)/SiO2/Si multi-films were carried out in the temperature range from 400◦C to 700◦C. Failure temperature and mechanism of Cu diffusion in CoMoB film were discussed. The composition, sheet resistance and morphology of the film were investigated by X-Ray Diffractometer (XRD), Four Point Probe (FPP) and Atomic Force Microscopy (AFM), respectively. It can be concluded that the failure temperature of CoMoB film is 600◦C. The main reason of failure is that a large number of Cu particles passed through CoMoB grain boundary and reacted with Si substrate to generate Cu4Si with high resistance.

Stain etching, one step metal assisted chemical etching (1-MACE) and two-step metal assisted chemical etching (2-MACE) were used for preparing porous silicon powders (PSPs) based on metallurgical silicon powder. The influences of different oxidants species and concentrations on the structure of PSP were discussed. The results indicated that the different oxidant species has an important effect on the morphology and structure of PSP. In stain etching, there is still a challenge for fabricating PSP with uniform and controlled pore size structure. In contrast, metal-assisted chemical etching method is easier to prepare PSPs sample with uniform depth and pore size than stain etching, In 1-MACE, the growth rate of the PSPs pore was between 0.05 and 0.10 μm/min, which is far less than that of 2-MACE (about 0.2~0.5 μm/min). Furthermore, 2-MACE showed more advantages than stain etching and 1-MACE in controlling of pore size range and structure.

Supplemental Digital Content is available in the text.

Ribosome-inactivating proteins (RIPs), a type of defensive chemicals, play key roles in host defense mechanisms against foreign pathogenic invaders and plant stress resistance. Alpha-momorcharin, a member of typical type I RIPs isolated from Momordica charantia, showed strongly antifungal, antitumor, and antibacterial activities both in vitro and in vivo. In this study, the expression level of alpha-momorcharin gene in response to environmental stress and phytohormones were examined through quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analyses. Results showed that α-momorcharin gene expression was up-regulated in response to salinity and osmotic stresses. Phytohormones, including abscisic acid and gibberellic acid, also enhanced α-momorcharin expression, while the expression level was not affected by salicylic acid. It’s speculated that the α-momorcharin gene might be functional in plant basal or defense resistance against environmental stresses, and it also involved in hormonal signaling pathways. This research might be exploited in further genetic engineering programs and plant protection.

Bacterial pathogens utilize gene expression versatility to adapt to environmental changes. Vibrio cholerae, the causative agent of cholera, encounters redox-potential changes when it transitions from oxygen-rich aquatic reservoirs to the oxygen-limiting human gastrointestinal tract. We previously showed that the virulence regulator AphB uses thiol-based switches to sense the anoxic host environment and transcriptionally activate the key virulence activator tcpP. Here, by performing a high-throughput transposon sequencing screen in vivo, we identified OhrR as another regulator that enables V. choleraerapid anoxic adaptation. Like AphB, reduced OhrR binds to and regulates the tcpPpromoter. OhrR and AphB displayed differential dynamics in response to redox-potential changes: OhrR is reduced more rapidly than AphB. Furthermore, OhrR thiol modification is required for rapid activation of virulence and successful colonization. This reveals a mechanism whereby bacterial pathogens employ posttranslational modifications of multiple transcription factors to sense and adapt to dynamic environmental changes.

The data sparsity and prediction quality are recognized as the key challenges in the existing recommender Systems. Most of the existing recommender systems depend on collaborating flitering (CF) method which mainly leverages the user-item rating matrix representing the relationship between users and items. However, the CF-based method sometimes fails to provide accurate information for predicting recommendations as there is an assumption that the relationship between attributes of items is independent and identically distributed. In real applications, there are often several kinds of coupling relationships or connections existed among users or items. In this paper, we incorporate the coupling relationship analysis to capture the under-discovered relationships between items and aim to make the ratings more reasonable. Next, we propose a neighborhood-based matrix factorization model, which considers both the explicit and implicit correlations between items, to suggest the more reasonable items to user. The experimental evaluations demonstrate that the proposed algorithms outperform the state-of-the-art algorithms in the warm- and cold-start settings.

The author designed a intelligential spray car of fruit tree, this support frame of worktable support the whole spraying arm in the course, its dynamic properties is important to determine the product quality and life. On the basis of three-dimensional modeling, The modal of dynamic that support frame was analysis and the first ten modal parameters (natural frequencies and mode shapes) was calculated by using ANSYS finite element of analysis software. Compared with Modal parameters by method and experimental modal analysis obtained, summarizes the higher modes of dynamic structure, and proposed modifications for the structure.

A technique for a reconditioning equalizer filter for non-constant envelope signals is described. The input to a transmitter chain is modified by a reconditioning equalizer filter, prior to being applied to the transmitter. The reconditioning equalizer filter modifies and smoothens the amplitude of the signal. The modified and smoothened signal has its peaks reduced which results in lower Crest Factor. The input to the reconditioning equalizer filter could be a baseband, intermediate frequency (IF) or radio frequency (RF) signal. When the signal is an IF or RF signal, it needs to be down-converted to baseband before being applied to the reconditioning equalizer filter. The reconditioning equalizer filter could be performed in a digital or analog domain.

The adult epicardium is a potential source of cardiac progenitors after myocardial infarction (MI). We tested the hypothesis that cardiomyocyte-specific overexpression of membrane-associated human stem cell factor (hSCF) enhances epicardial activation, epicardium-derived cells (EPDCs) production, and myocardial arteriogenesis post MI.

The implementation of a project contains a lot of uncertainty, by their nature, random uncertainty, uncertainty and human factors (such as peoples limitations of understanding things and design methods, the use of analog approximate calculation results) due to the uncertainty of the future to better improve the structural reliability, this paper, the probability model reviewed structural reliability.

The real-time capacity-increase technology of transmission lines is adopted to increase transmission current capacity of transmission lines, by which the conductor temperature, the ambient temperature and the wind speed can be timely measured and the transmission current capacity can be adjusted dynamically without breach of available rules. A new type of Morgan's transmission line dynamic capacity-increase model is established, which can fast and effective computing the current line transmission capacity, and the transient running formula of transmission lines is established, the mathematical relationship between the conductor allowable temperature and the variety of sag of the span is presented, and the application of the monitoring device is introduced, it has important significance to research the power grid transmission interface dynamic capacity-increase technology.

The system uses the latest computer and RFSN induction smart card technology, with the principles of scientific, advanced, reliable and economy, and it is developed on the basis of many factors. Installing a set of import and export management facilities on the Entrances and exits of the parking lot, parking spaces will form a relatively closed space. When the vehicle is entering or exiting, the system captures images and recognizes vehicle license automatically etc,to make video surveillance of vehicles, real-time recording Vehicle access images, accounting, and so forth. It will be an effective work to control, monitor, and manage parking lot, reducing the operating costs of the parking lot, and to prevent steal vehicle behavior, which protects the interests of management and owners. Keywords: Program; Automation; RFSN

The construction of intelligent industrial park is an important part of intelligent power grid construction, and also a specific part in the national "Twelfth Five-year Plan". The development of the Internet of things is complementary to the construction of intelligent power grid, and also the key technology in the construction of intelligent park. With the development of software and hardware, the Internet of things will be more widely used in the construction of intelligent park.

Spray distribution uniformity is a very important performance of nozzle. This paper analyses the spray uniformity of the spraying machinery as well as the influence factors. Spray distribution coefficient of variation of nozzles varies with the different spray pressure, spray pressure and spacing. The nozzles of lechler ST made in German were tested to present the optimum spray height with different spray pressure and spray spacing through analyzing the trend of coefficient of variation varying with the different spray pressure, spray height and spray spacing. By the test, the greatest impact on spray uniformity is the pressure of the spray bar, followed by the height and the spacing of the spray bar. By analysis of the spray distribution coefficient of variation, we find the optimum combination of the spray pressure, spray height and spray spacing.

In natural product chemistry, it is often crucial to determine sugar composition as well as the absolute configuration of each monosaccharide in glycosides. An ultra-performance liquid chromatography method using both photodiode array (PDA) and mass spectrometry detectors (UPLC-UV/MS) was developed for qualitative analysis of the absolute configuration of monosaccharide enantiomers. Within a single injection, 16 monosaccharide derivatives including 6 pairs of aldose enantiomers (D/L-glucose, D/L-galactose, D/L-allose, D/Larabinose, D/L-xylose, and D/L-fucose) and 4 other monosaccharides (L-rhamnose, 2-deoxy-D-glucose, 6-deoxy-D-glucose, and 2-deoxy-D-glalactose) were identified in less than 25 minutes. It was found that the structures of derivatives of sugar enantiomers correlated with retention time. Among derivatives of sugar enantiomers in the current study, the stereoisomer of R-configuration at C-3' retained longer than the corresponding S-configuration isomer. The UPLC-MS method can increase sensitivity of detection of the saccharides by more than 10 times compared to previously reported methods. The one-pot reaction of monosaccharide with L-cysteine methyl ester and phenyl isothiocyanate is easily reproduced, clean, and relatively simple in a screwcapped reaction vial. The developed method was successfully applied for the analysis of different types of glycosides, viz., glycosides of triterpenes, steroids, and flavonoids, that commonly exist in nature. The absolute configurations of composed monosaccharides are clearly characterized from tested samples. [ABSTRACT FROM AUTHOR]

Maximum likelihood estimation (MLE) is a commonly used method of Weibull distribution, but it needs to calculate the transcendental equations which is based on the computer programming. In this paper, we established a new MLE model of Weibull distribution in a case of random censoring. And this model was proved feasible and correct via three examples. At the same time, the model can be used for a variety of censored data and complete life data of Weibull distribution of MLE.

The universal tool microscope is widely applied in geometric measurement, as the imaging method is a typical measurement methods. In this paper, data processing and calculation example to specify the method of image measurement of the external thread, Classifications have been carried out systematically in this paper on the origin of error of the universal tool microscope, the image- measuring methods was summarized.

The comparative analysis of a parabolic and hyperbolic flexible hinges were presented. The closed-form compliance equations in the working and non-working plane can be derived by using the Castigliano’s second theorem. In order to compare the relative performance of parabolic and hyperbolic flexure hinges, a ratio function between specific compliances of the two hinges is defined. We analyzed the non-dimensional ratios of working plane and non-working plane compliance to show the relative properties of parabolic versus hyperbolic flexure hinges. The analysis results has showed compared to a hyperbolic flexure, a parabolic flexure can produce more desired output and is slightly less sensitive to axial effects under identical loading conditions. Meanwhile, the comparative study on the parabolic and hyperbolic flexure hinges can provide a theoretical basis for choosing them.

Considering the effects of structural sizes of a parabolic flexible joint on its performance, compliance, sensitivity and accuracy analysis are performed in this paper. The closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions, and accuracy equations are also obtained by using the Castigliano’s second theorem. According to the closed-form compliance equations, the effects of the structural parameters, such as thickness, notch depth, length and width, on the compliance of flexible joint are analyzed, respectively. In order to explore the effects of variations of the structural parameters on its compliance, the sensitivity analysis is carried out. And the accuracy analysis of the parabolic flexure joint is performed. The analysis results have shown that the parameters have large influence on in-plane compliance, and have small effects on out-of-plane one. And changes of compliance are larger within initial small range of parameters, while it has small variation in larger size range. And the length of joint has no effect of sensitivity

A discrete sliding mode control based on reaching law is investigated to suppress vibration of high-speed flexible manipulator. The finite element method and experimental modal test is applied to obtain the dynamic model of the system. Due to the influence from uncertain external disturbances and measurement noise, and uncertain parameters, sliding mode control has invariance of the sliding mode. The discrete sliding mode control approach with reaching law is applied to design the vibration controller which enables the system to be zero state as the system states are away from the equilibrium one due to external disturbances. The discrete Kalman filtering technique is employed to construct state estimator because the state variables cannot be directly measured. The first three natural frequencies and damping ratio are obtained by using experimental modal testing. The experimental control system is constructed and experimental validation is carried out using dSPACE real-time simulation system and MATLAB/Simulink. The experimental results showed that the proposed controller can effectively suppress the vibration response of the flexible manipulator.

The vibration of a complicated pipeline connected with centrifugal pump has been studied by ANSYS. The first 32 natural frequencies and the first five modal shape of the pipeline system is obtained by Modal analysis. The result shows that its excited frequency is close to the 30th natural frequency of the pipeline system，which will result in resonance. Because excited force caused by pulsatile fluid in pipe can make pipeline to has a compulsive vibrations, harmonic respones analysis is used to determine continuous dynamic characteristics of pipeline. The critical frequencies of node with the maximal amplitude at 30th modal shape are 12.452Hz and 56.284Hz by investigating its spectrum image of displacement. The major principal stress at two critical frequencies, far exceeding the yield strength of material, is respectively -1223MPa and 621 MPa, which demonstrates that the pipeline are very incidental to be destroyed.

Experimental study on ultrasonic and electromagnetic roll-casting of magnesium alloy was carried out using a self designed and installed twin roll continuous horizontal caster . 2.5mmthickness and 200mmbreadth of AZ31B magnesium alloy casting strips were produced successfully. The results show that the ultrasonic and electromagnetic field is transferred into roll-casting zone and result in a great decrease of the grain size,the average grain size has decreased to 10～15μm from 60～70μm; and also improved the mechanic properties of the AZ31B magnesium alloy sheet, the tensile strength and yield strength and elongation and hardness are improved by 25%and 44.4% and 120.7% and 12%respectively. On this basis, the mechanism of grain refinement during cast-rolling process with ultrasonic cavitation and electromagnetic field effect are discussed.

An optimization design method of a hyperbolic flexible hinge is presented in this paper. According to the structure feature and force exerted on the flexible hinge, the closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions by using the Castigliano’s second theorem. Meanwhile, the accuracy equations of the hyperbolic flexure hinge are obtained using the Castigliano’s second theorem. The in-plane rotation angle of flexure hinge is optimization objective, and the constraints of optimization model are out-of-plane displacements and one described the accuracy of hinge, such that the optimization model can be established to meet performance requirements of flexure hinge. Based on the optimization model, the optimization designs of hyperbolic flexure hinge are performed to acquire its optimized structural parameters. And the optimization results have showed the optimization process can meet the design requirement.

Cavitation typically occurs when the fluid pressure is lower than the vapor pressure at a local thermodynamic state. The aim of this paper is a numerical investigation of the cryogenic cavitation flow characteristics, considering variable thermodynamic properties of liquid nitrogen and numerical simulation liquid nitrogen around hydrofoil cryogenic cavitation flow characteristics. Based on homogeneous flow model and Zwart cavitation model, calculates hydrofoil isothermal and cryogenic cavitation in liquid nitrogen steadily, updates the evaporation and condensation coefficients of Zwart cavitation model, gives the hydrofoil surface pressure profile, temperature depression and distribution of cavitation intensity, contrasts the isothermal and cryogenic cavitation flow characteristics. Numerical results show that thermodynamics effect in cryogenic liquid cavitation significantly. Meanwhile, the hydrofoil surface pressure and temperature numerical results with experimental data and more Hord compared to verify the validity of the numerical simulation.

Considering the increasingly wider applications of flexible hinge in the fields of micro-electromechanical and micro-positioning etc., the optimal design method of a parabolic flexible hinge is presented. According to the structure feature and force exerted on the flexible hinge, the closed-form flexibility expressions in the working and non-working plane can be derived by using the Castigliano’s second theorem. Meanwhile, the accuracy analysis of the parabolic flexure hinge is performed. The rotation angle of flexure hinge in the working plane is treated as objective function, and the constraints of optimization model are displacements in the non-working plane and one described the accuracy of hinge, such that the optimization model expressed performance requirements of flexure hinge can be established. Based on the optimization model, the optimization designs of parabolic flexure hinge are accomplished to acquire the optimized structural parameters. In conclusion, the study on the optimization design of the parabolic flexure hinge can provide a theoretical basis for its engineering applications

In order to the effects of structural sizes of a hyperbolic on its performance, sensitivity and accuracy analysis are performed in this paper. According to the structure feature and force exerted on the flexible hinge, the closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions by using the Castigliano’s second theorem. Meanwhile, the accuracy equations are obtained using the Castigliano’s second theorem. According to the closed-form flexibility formulas, the effects of the four structural parameters, such as thickness, notch depth, length and width, on the flexibility of flexible hinge are analyzed, respectively. In order to study further the effects of the structural parameters on its flexibility, we derive the sensitivity equations, and the sensitivity analysis is carried out. Meanwhile, the accuracy analysis of the hyperbolic flexure hinge is performed. The analysis results have shown that the parameters have large influence on in-plane compliance, and have small effects on out-of-plane one. And the changes are larger within initial small range of parameters, while be small variation in larger size range. And the length has no effect of sensitivity.

Electrical conductivity of silicon nanomembranes (SiNMs) was measured by van der Pauw method under two surface modifications: hydrofluoric acid (HF) treatment and vacuum-hydrogenated(VH) treatment, which create hydrogen-terminated surface; and one interface modification: forming gas (5% H2 in N2) anneal, which causes hydrogen passivated interfaces. The results show that thinner SiNMs are more sensitive to the surface modifications, and HF treatment can cause larger drop of sheet resistance than that caused by VH treatment probably because of Fluorine (F). Forming gas anneal can also improve the conductivity depending on the interface trap density.

The Al-40Si alloy modified by 1.0 wt% Sr addition was heat-treated using L9(34) orthogonal test. The mechanical properties were measured. The microstructures were analyzed using optical microscope. After heat treatment, the hardness decreases about one times. The eutectic matrix and primary Si phase are both refined. The primary Si phase is refined and homogeneously distributes in the matrix with the solution temperature and time increasing. The optimal heat treatment condition is that the solution temperature, solution time, aging temperature, and aging time are 550 ℃, 18 hours, 200 ℃, and 5 hours, respectively. In addition, the theoretical optimal value for the hardness is 20.6 HRC, which is coherent with the practical optimal value.

In this paper, the Standard k- ε equation turbulence model was used to simulate three-dimensional flow over a spillway. The volume of fluid method (VOF) was introduced into the iteration of calculation to solve the free water surface, and segregated solver was used with the PISO pressure-velocity coupling scheme. The free surface, the magnitude and distribution of the velocity, the pressure on the spillway surface and so on were obtained. The simulation results were in good agreement with the experiment data.

In this paper, polyacrylic acid (PAA)/TiO2 nanocomposites with photocatalytic activity were prepared via in-situ growth of anatase TiO2 nanoparticles in polyacrylic acid matrix using a simple hydrothermal method. First, water-soluble titania xerogel was prepared by a modified sol-gel procedure involving hydrolyzation of titania precursor, tetra-n-butyl titanate (TBT), in trifluoroacetic acid solution. Then, titania xerogel was dissolved in water and formed a homogeneous solution. Sequentely, polyacrylic acid as an adsorbed polymer was put into the solution and a hydrogel containing titania xerogel was obtained. After hydrothermal treatment for 10h at 100 C, polyacrylic acid/TiO2 nanocomposites were obtained. The structure and morphology of as-prepared samples were characterized by Raman, SEM, and TEM. The photocatalytic activity of nanocomposites was evaluated by photodegradation of methyl orange under UV irradiation. The result showed that TiO2 nanocomparticles in anatase phase was in-situ generated inside PAA matrix and revealed a high photocatalytic activity, which can be used in environment purification and water treatment.

The Ge mole fraction (x) of Si1-xGex layer was described by the C-V technique for Schottkey contact of single heterojunction Si1-xGex/Si, whose structure profile can be characterized by SEM image and EDS. Then the strained Si cap layer was grown on the Si1-xGex/Si, and C-V technique was used to determine the carrier concentration and structure of double heterojunction Si/Si1-xGex/Si. The change of the structure between Si1-xGex/Si and Si/ Si1-xGex/Si was also observed by this method.