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In order to solve the problems of low precision and high time cost in operational modal analysis for linear slow time-varying (LSTV) structures, a moving window incremental multidimensional scale analysis (MWIMDS) method is proposed in this paper. Based on the time-freezing theory and the moving window technique, in each window, the non-stationary random vibration signals are regarded as stationary random time series, and the LSTV structure is regarded as linear time-invariant structure. Firstly, the low dimensional matrix corresponding to the modal coordinate response matrix is obtained by using multidimensional scale analysis (MDS) for stationary random vibration response signals. Then, the natural frequencies are identified from the modal coordinate response matrix by using the single degree of freedom technique. Secondly, the least square generalized inverse is used to substitute the identified modal coordinate response matrix into the vibration response signal to estimate the modal shape matrix. Finally, when the fixed-length window is moved to the next window, the increment is applied to the MDS by removing the first time series point data, adding the latest time vibration response signal data, and calculating the distance between the new time point and other sequence points without recalculating all sequence points. Incremental can greatly reduce the time complexity of the algorithm. MDS is a linear global dimension reduction algorithm. Identification results on simulation dataset of three-dimensional cylindrical shell structure and the experiment dataset of steel cantilever beam structure verify that the MDS-based operational modal analysis has the advantages of good robustness and high identification accuracy. Identification results on the simulation dataset of mass slow time-varying with three degrees of freedom verify that MWIMDS-based operational modal analysis can identify modal shapes and natural frequencies only from non-stationary random vibration signals for LSTV structure well, and the identification accuracy of modal shapes is better than the moving window principal component analysis method and moving window neighborhood preserving embedding. The time and space cost of MWIMDS-based operational modal analysis are lower than that of the moving window multidimensional scale analysis based operational modal analysis without incremental.

Deep-sea hydrothermal vents are known as chemosynthetic ecosystems. However, high temperature vents emit light that hypothetically can drive photosynthesis in this habitat. Metagenomic studies have sporadically reported the occurrence of phototrophic populations such as cyanobacteria in hydrothermal vents. To determine how geographically and taxonomically widespread phototrophs are in deep-sea hydrothermal vents, we collected samples from three niches in a hydrothermal vent on the Southwest Indian Ridge and carried out an integrated metagenomic analysis. We determined the typical community structures of microorganisms found in active venting fields and identified populations of known potential chlorophototrophs and retinalophototrophs. Complete chlorophyll biosynthetic pathways were identified in all samples. By contrast, proteorhodopsins were only found in active beehive smoker diffusers. Taxonomic groups possessing potential phototrophy dependent on semiconductors present in hydrothermal vents were also found in these samples. This systematic comparative metagenomic study reveals the widespread distribution of phototrophic bacteria in hydrothermal vent fields. Our results support the hypothesis that the ocean is a seed bank of diverse microorganisms. Geothermal vent light may provide energy and confer a competitive advantage on phototrophs to proliferate in hydrothermal vent ecosystems.

In this paper, water-soluble CdTe quantum dots (QDs) with different sizes from 3 to 3.9 nm are synthesized by the aqueous phase method using glutathione as the stabilizer, and their fluorescence properties below the freezing point are studied. The results show that the QD dispersion system still maintains the liquid state at −30 °C when the volume fraction of ethanol is 30%, and its fluorescence has a strong temperature dependence below the freezing point; as the temperature decreases from 0 to −30 °C, the fluorescence intensity increases about 62–82%, and the fluorescence emission peak also blue-shifts (5–10 nm). After cycles of heating (0 °C)–cooling (−30 °C), the fluorescence intensity can still be recovered, indicating a strong fluorescence reversibility. This work provides help for expanding the application of QDs in the fields of biomedicine.

Thunberg fritillary bulb (the dry bulbs of Fritillaria thunbergiiMiq.), a traditional Chinese Medicine, is widely applied as an expectorant and antitussive. In this investigation, the primary metabolites of bulbs, flowers, leaves, and stems of F. thunbergiiwere analyzed by gas chromatography–mass spectrometry. Principal component analysis, partial least squares-discriminate analysis, orthogonal projection to latent structures-discriminate analysis, and heat map analysis showed that there were dissimilar metabolites, and a negative correlation between amino acids and saccharides in different analytes. Furthermore, carbodiimide, tryptophan, glucose-6-phosphate, xylose, 2-piperidinecarboxylic acid, monoamidomalonic acid, phenylalanine, and histidine were found to play an important role in the plant metabolism net of F. thunbergii.

Three novel donor–acceptor alternating polymers containing ladder-type pentacyclic heteroacenes (PBo, PBi, and PT) are synthesized, characterized, and further applied to organic field effect transistors (OFETs) and polymer solar cells. Significant aspects of quinoidal characters, electrochemical properties, optical absorption, frontier orbitals, backbone coplanarity, molecular orientation, charge carrier mobilities, morphology discrepancies, and the corresponding device performances are notably different with various heteroarenes. PTexhibits a stronger quinoidal mesomeric structure, linear and coplanar conformation, smooth surface morphology, and better bimodal crystalline structures, which is beneficial to extend the π-conjugation and promotes charge transport via 3-D transport pathways and in consequence improves overall device performances. Organic photovoltaics based on the PTpolymer achieve a power conversion efficiency of 6.04% along with a high short-circuit current density (JSC) of 14.68 mA cm–2, and a high hole mobility of 0.1 cm2V–1s–1is fulfilled in an OFET, which is superior to those of its counterparts, PBiand PBo.

The pericarp of Trapa natansL., an annual aquatic floating herb belonging to Lythraceae family, is used as a folk medicine in China. In this study, extracts of Trapa natanspericarp were tested both in vitroand in vivothrough a high-fat diet with a single medium dosage streptozotocin injection induced type 2 diabetic mice. Different solvent extracts of Trapa natanspericarp showed α-amylase and α-glucosidase inhibitory activity. After four weeks administration, the ethyl acetate extract of Trapa natanspericarp (50 and 100 mg/kg b.w.) reduced fasting blood glucose level, ameliorated oral glucose tolerance and insulin resistance, improved serum lipids alterations in type 2 diabetic mice as well. Additionally, ethyl acetate extract significantly elevated the insulin receptor substrate 1 and Akt serine/threonine kinase phosphorylation compared to diabetic group. HPLC-MS and HPLC-DAD analysis showed that the ethyl acetate extract was rich in hydrolysable tannins. Results support the notion that Trapa natanspericarp extract has a potential hypoglycemic activity.

The quantitative analysis of amino acids, nucleosides and nucleobases is important for the quality evaluation of the popular fruit Annona squamosaL. obtained from different regions in China. To establish a repeatable and accurate LC-QTRAP-MS/MS method for the simultaneous determination of 23 target components in fruitages obtained from 5 different regions, chromatographic separation was carried out on an amide column with gradient elution using water and acetonitrile. The method is rapid and completed in less than 6 min and has acceptable linearity in the range of the tested concentration. The average recoveries of the 23 components were 95.30–104.53% with the relative standard deviations of 1.01–3.90%. The results show that the qualities of AAs and NNs in the A. squamosafruit obtained from the Guangxi province are optimal. The contents of these targets in the Annona squamosafruitages obtained from 5 regions are significantly different, which might be due to their environment and species.

Owing to the satellite signal strengths of GNSS is so low that it is interfered with powerful signal, that how to effectively resist interference is becoming a problem.In this paper,first LCMV algorithm based on the power-inversion adaptive array is deduced from theory in certain mathematical model ,what’s more ,for avoiding computing the inverse of matrix, LCMV algorithm is improved and then is verified through the Matlab-simulation .Last,the hardware design is given for the realization of this algorithm.

This paper mainly analyzed the security of AES(Advanced Encryption Standard) protocol and virtual private network technology ,the network 802.3 and 802.1x/EXP security vulnerabilities: defects of Service Set Identifier and MAC Address Filtering, defects of User Authentication Method, security vulnerabilities of WPA Algorithm, defects of 802.1x / EAP and RADIUS Authentication, etc. The authentication and encryption method to improve network security measures.

The microprocessor generates many digital noises that find their way back from the clock reference input of the microprocessor to the reference clock lines with which the RF circuits are sharing. These digital noises are conductively coupled to the RF circuits, including any RF transceiver, Bluetooth module and other RF circuits, such as a local oscillator and phase locked loop circuits, to cause spurious signals and jitters in the circuits, which in turn, degrade the RF performance or cause a radio to fail certain specifications.

Electrodes are expensive consumables of electrophysiological experiments. Cheap and homemade microwire electrodes have been widely applied, but their implantation performance is not good. To fabricate low cost and acceptable performance of microwire electrode, first, we analyzed the key factors affecting the long-term recording performance and determined the direction of the enhancement of electrode. We improved the existing fabrication process through electrode fabrication and the electrode tip surface modification, and systematically evaluated its properties, signal acquisition ability and biocompatibility. The result shows that the improved electrode tip surface is smooth and tidy, and its impedance decreased by 56.1% on average; record signal-to-noise ratio is higher; recording longevity reached 45 days; biocompatibility is better. It can meet the use of the general electrophysiological experimental, and electrode fabrication cost is less than 58 yuan.

Forward osmosis is an emerging membrane technology with potential applications in desalination and wastewater reclamation, osmotic pressure gradient cross the FO membrane is used to generate water flux. In contrast with conventional pressure-driving membrane process, the advantage of FO is significant: energy saving, high solute rejection and low fouling propensity. In this study, alginic acid (AA), boving serum albumin (BSA), humic acid (HA) and tannic acid (TA) were used to investigate the influence of organic fouling. The flux changed obviously, the rejection was approving and the absorption of organics was observed in the study. Ultrasonic oscillation was employed to wipe the organics off the fouling membranes, which was intend to study the quality of absorption of organic matters.

The interval estimation for the presumption of structure concrete strength should be gained because of strong randomness of test data. For further exaltation of accuracy and credibility test concrete strength, analytic solution of inverse regression equation for evaluating concrete strength of building materials is presented herein based on the inverse regression model. The accurate solution for the presumption of concrete strength can be obtained through the analytic solution, detection precision and reliability for the presumption of structure concrete strength can be improved with respect to the traditional point estimation method.

The basic theory of the rebound method is introduced, and analytic solution of inverse regression equation for evaluating concrete strength of building materials is presented herein based on the inverse regression model. Furthermore, two engineering examples are given, satisfactory results are obtained using the analysis method. The analysis method can be also used to gain the presumption of strength for others building materials and solutions of other inverse regression models.

The present study aimed to detect serum fetuin-A levels in knee osteoarthritis (OA) patients and to investigate their correlation with clinical severity. We enrolled 215 knee OA patients and 76 healthy controls. We measured serum fetuin-A levels by enzyme-linked immunosorbent assay and assessed the correlation between serum fetuin-A levels and Kellgren-Lawrence grades as well as Western Ontario and McMaster Universities Arthritis Index scores in OA patients. Our results demonstrated that serum fetuin-A levels were independently and negatively correlated with greater clinical severity in OA patients.

To achieve high density and high performance, through-Silicon Vias (TSVs) have recently aroused much interest because it is a key enabling technology for three-dimensional (3-D) integrated circuit stacking and silicon interposer technology. In this study, a 3-D 1/8th symmetrical nonlinear finite element model of a stack die TSV package was developed using ANSYS finite element simulation. The model was used to optimize the package for robust design and to determine design rules to enhance 3-D stack package in view of bump reliability. An L8(2×7) Taguchi matrix was developed to investigate the effects of interposer thickness, TSV diameter, insulation (SiO2) thickness, chip thickness, substrate thickness, bump height, and bump diameter on bumps reliability. A temperature cycling test in the range of 0 °C to 100 °C was conducted by three cycles. The mechanical property of SAC leadless solder included time independent plastic and time dependent creep behaviors. The parameter of inelastic strain range of the third cycle was used to evaluate the bump life prediction. Two levels were chosen for each parameter to cover the ranges of interest. The results show that the smaller insulation (SiO2) and substrate thickness and the larger dimension for the other factors provide the best combination. These could be used as guides for further similar 3-D stack packages design.

A new constructive method is proposed for the concrete strength of existing building. Nondestructive test methods for existing buildings had been widely accepted in practical engineering, the1ower and upper confidence limits are given by using the inverse regression method, then a strong-weak qualified constructive method is presented according to the confidence limits. More rational constructive results of concrete strength can be obtained than the custom methods. Furthermore, an example of practical engineering is given. The results showed that the constructive method can provide reference value for the actual engineering, establish foundation for further emendation of “technical specification for inspection of concrete compressive strength by the nondestructive methods”.

Existing sintering machine for controlling of arch camber is not ideal. The usual way is by means of the hydraulic system to balance the excess thrust what is caused arching. For this reason, the paper considers to change the structure layout of belt sintering machine ,so that eliminate the arch camber by itself. So improvement of process layout of 60㎡ sintering machine has been made, and thus deduced the expression and got the limen formula of the thrust force which the back sprocket wheel drive lower pallet cars. At the same time, through the analysis and compute got driving moment of lower pallet cars, which caused by four pallet cars from back sprocket wheel. According to equation of mechanical equilibrium to eliminate the arch of pallet cars, determine the suitable angle after sintering machine has been improved to solve the problem about arch pallet cars completely.

Three new bistetrahydrofuran annonaceous acetogenins (1–3) were isolated from a 95% EtOH extract of Annona squamosaseeds. Four known annonaceous acetogenins, uvarigrandin A (4), bullatacin (5), squamostatin-A (6), and squamostatin-D (7), were also isolated. Their structures were elucidated by spectroscopic analyses, and the absolute configurations of the carbinol centers of 1–3were defined by application of the Mosher method. These compounds all exhibited significant cytotoxic activity in vitro against five human tumor cell lines.

Abstract. Xinjin technology group company is to provide professional electronics manufacturing services ( EMS ) Company. The main business is the assembly of PCB and small electronic products and packaging They are the main problem facing the enterprise that global oversupplies in the market, which includes cost saving, protection of the environment and improve efficiency.There are three primary aspects in this paper. They are electric circuit capacitance compensation, tin slag recycling and type U reconfigurable production line. They were to take the new technology, new production process to replace outdated., Profits were improved through these reform measures.

Wavelet analysis, as a new kind of time-frequency representation technique, has made great progress recently and been applied widely in different engineering practice. To solve the problem of full-wave Fourier algorithm which is disable to filter decaying DC component and has worse frequency characteristic, it is presented an improved algorithm depending on the combination of subtraction filter and full-wave Morlet complex wavelet, to get out the fundamental wave amplitude of the current in the distribution line, by studying each parameter’s influence on the performances of Morlet complex wavelet algorithm. It can filter decaying DC component efficiently and has better frequency characteristic.

Measurements of pNa with the glass-membrane ion-selective electrode in unbuffered aqueous solutions require care in the constitution of the measuring cell, because of varialbe liquid-junction potentials at the salt bridge. Of the bridge electrolytes tested, with calomel or silver/silver chloride reference electrodes, 3 M ammonium chloride in agar-agar gel was most satisfactory. Calibration graphs were of almost theoretical slope in the range 10−3−5 × 10−1M sodium ion.

In this study, two different designs of liquid metal fast reactor (LMFR) fuel rods wire-wrapped and non-wire-wrapped (bare) are compared with respect to different parameters as a means of considering the optimum fuel design. Nuclear seismic rules require that systems and components that are important for safety must be capable of bearing earthquake effects, and that their integrity and functionality should be guaranteed. Mode shapes, natural frequencies, stresses on cladding, and seismic aspects are considered for comparison using ANSYS. Modal analysis is compared in a vacuum and in lead–bismuth eutectic (LBE) using potential flow theory by considering the added mass effect. A simple and accurate approach is suggested for the determination of the LBE added mass effect and is verified by a manually calculated added mass, which further proved the usefulness of potential flow theory for the accurate estimation of the added mass effect. The verification of the hydrodynamic function (τ) over the entire frequency range further validated the finite element method (FEM) modal analysis results. Stresses obtained for fuel rods against different loading combinations revealed that they were within the allowable limits with maximum stress ratios of 0.25 (bare) and 0.74 (wire-wrapped). In order to verify the structural integrity of cladding tubes, stresses along the cladding length were determined during different transients and were also calculated manually for static pressure. The manual calculations could be roughly compared with the ANSYS results, and the two showed a close agreement. Contact analysis methodology was selected, and the most appropriate analysis options were suggested for establishing contact between the wire and cladding for the wire-wrapped design grid independence analysis, which proved the accuracy of the results, confirmed the selection of the appropriate procedure, and validated the use of the ANSYS mechanical APDL code for LMFR fuel rod analysis. The results provided detailed insight into the structural design of LMFR fuel rods by considering different structural configurations (i.e., bare and wire-wrapped) in the seismic loading; this not only provides a FEM procedure for LMFR fuel with complex configuration, but also guides the reference design of LMFR fuel rods.