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University has been based on the entrepreneurial spirit in the local economy. According to the survey, ecosystem components play an integral role in their evolution in the ecosystem's relative economic modeling. To achieve the expected research goals are, the body's literature; has focused on the theoretical support for the interconnected components of the ecosystem of innovation and entrepreneurial spirit of the University of Economics in the region directly below. Also, throughout the whole investigation's hypothetical structure, this proposition's endeavors will show the possible hole of raised information from two serious issues in this environment. Model unusual organization traffic recognition strategy and framework has been Support Vector Machine proposed. By coordinating the information parcels with a similar stream, can diminish the framework's overhead preparation. Suggest that utilize a discovery calculation for distinguishing an adjustment in the process to assault the traffic design. The calculation likewise permits to distinguish the new port number's utilization to recognize this sort of assault or altered payload and mark-based framework by a variation of the assault. Further, the calculation verifies that it has neglected to pass the review to be restricted to the gathered data, and the assault is recognized throughout the traffic data. Proposed a location plan of stream-based strange organization traffic. It utilizes this calculation.

For enhancing the 2.0 μm band fluorescence of Ho3+, a certain amount of WO3 oxide was introduced into Ho3+/Tm3+/Yb3+ tri-doped tellurite glass prepared using melt-quenching technique. The prepared tri-doped tellurite glass was characterized by the absorption spectra, fluorescence emission and Raman scattering spectra, together with the stimulated absorption, emission cross-sections and gain coefficient. The research results show that the introduction of WO3 oxide can further improve the 2.0 μm band fluorescence emission through the enhanced phonon-assisted energy transfers between Ho3+/Tm3+/Yb3+ ions under the excitation of 980 nm laser diode (LD). Meanwhile, the maximum gain coefficient of Ho3+ at 2.0 μm band reaches about 2.36 cm-1. An intense 2.0 μm fluorescence emission can be realized.

Improving the spectroscopic properties of rare earth (RE) doped glass materials is a challenging task. In the present work the metallic silver nanoparticles (Ag NPs) were embedded into Er 3+ /Yb 3+ codoped tellurite glasses with composition TeO 2 –Bi 2 O 3 –TiO 2 , prepared using melt-quenching and subsequent heat-treated techniques, and the improved effect of Ag NPs on the 1.53 μm band fluorescence of Er 3+ ions was investigated. About 24 h heat-treatment of Er 3+ /Yb 3+ codoped tellurite glass containing 1 mol % amount of AgNO 3 at the temperature 370 °C yielded the well-dispersed and near-spherical Ag NPs with ∼11.4 nm average diameter as evidenced by transmission electron microscopy (TEM) image. The intense 1.53 μm band fluorescence was observed in the prepared Er 3+ /Yb 3+ codoped tellurite glasses under the excitation of 980 nm and was further improved with the presence of Ag NPs in the glass matrix, which is attributed to the enhanced local electric field around doped RE ions induced by Ag NPs and the possible energy transfer from Ag NPs to Er 3+ ions. The enhanced local electric field was well demonstrated by comparing the variation of emission spectra of hypersensitive probe Eu 3+ ions in tellurite glasses with and without Ag NPs. From the Judd-Ofelt analysis, it was also found that the value of Ω 6 intensity parameter increased slightly with the increase of Ag NPs concentration in a certain range, also confirming the possibility of realizing strong fluorescence emission. In addition, the amorphous structural nature was demonstrated by the measured X-ray diffraction (XRD) patterns with no sharp diffraction peak. The enhanced 1.53 μm band fluorescence indicates that the Er 3+ /Yb 3+ codoped tellurite glass with an appropriate amount of Ag NPs is a promising candidate for the development of Er 3+ -doped fiber amplifiers (EDFAs) applied in the WDM systems.

Recently, hydroxyl-carbonates have drawn increasing interest in energy storage because of their special layered structure and pseudocapacitive character. In this work, a novel open architecture based on reduced graphene oxide and ultra-fine single-crystal Co2(CO3)(OH)2 nanowires (designed as rGO/Co2(CO3)(OH)2) is synthesized via mutual electrostatic interactions benefiting from their intrinsic opposite charges. Taking advantage of the high conductivity of rGO, the ultra-fine diameter of the nanowires, and the open network of the architecture, the rGO/Co2(CO3)(OH)2 electrode exhibits high specific capacitance (998 F g−1 at 1 A g−1 and 727 F g−1 at 20 A g−1) with excellent rate capability and stability (98.3% capacitance retention after 4000 cycles). An asymmetric supercapacitor fabricated by using it as the positive electrode and activated carbon as the negative electrode has demonstrated high energy/power density (26.7 W h kg−1 at 751 W kg−1 and 13.1 W h kg−1 at 15 362 W kg−1) and outstanding cycle stability (10 000 times with only 5.4% loss).

The metallic silver nanoparticles (NPs) was introduced into the Er3+/Ce3+/Yb3+ tri-doped tellurite glasses with composition TeO2–ZnO–La2O3 to improve the 1.53 μm band fluorescence. The UV/Vis/NIR absorption spectra, 1.53 μm band fluorescence spectra, fluorescence lifetimes, X-ray diffraction (XRD) curves, differential scanning calorimeter (DSC) curves and transmission electron microscopy (TEM) image of tri-doped tellurite glasses were measured, together with the Judd–Ofelt intensity parameters, emission cross-sections, absorption cross-sections and radiative quantum efficiencies were calculated to investigate the effects of silver NPs on the 1.53 μm band spectroscopic properties of Er3+ ions, structural nature and thermal stability of glass hosts. It is shown that Er3+/Ce3+/Yb3+ tri-doped tellurite glasses can emit intense 1.53 μm band fluorescence through the combined energy transfer (ET) processes from Yb3+ to Er3+ ions and Er3+ to Ce3+ ions under the 980 nm excitation. At the same time, the introduction of an appropriate amount of silver NPs can further improve the 1.53 μm band fluorescence owing to the enhanced local electric field effect induced by localized surface Plasmon resonance (LSPR) of silver NPs and the possible energy transfer from silver NPs to Er3+ ions, and an improvement by about 120% of fluorescence intensity is found in the studied Er3+/Ce3+/Yb3+ tri-doped tellurite glass containing 0.5 mol% amount of silver NPs with average diameter of ∼15 nm. The energy transfer mechanisms from Yb3+ to Er3+ ions and Er3+ to Ce3+ ions were also quantitatively investigated by calculating energy transfer microparameters and phonon contribution ratios. Furthermore, the thermal stability of glass host increases slightly with the introduction of silver NPs while the glass structure maintains the amorphous nature. The results indicate that the prepared Er3+/Ce3+/Yb3+ tri-doped tellurite glass with an appropriate amount of silver NPs is an excellent gain medium applied for 1.53 μm band EDFA pumped with a 980 nm laser diode (LD).

Hierarchical porous architectures assembled by ultrathin mesoporous nanosheets are attractive for electrochemical energy storage. Herein, we present a facile and scalable strategy where two ultrathin mesoporous NiCoO2 sheets (∼2 nm) are anchored on both sides of a rGO sheet to form an ultrathin sandwich nanosheet (∼6 nm) using a chemical co-precipitation method. The sandwich nanosheets are randomly wrinkled, thus the framework built up by such sheets is porous and has a high specific surface area. The high quality rGO endows the composite with excellent conductivity. And the firm adhesion between the NiCoO2 sheet and flexible rGO also guarantees the integration of the electrode during electrochemical cycling. The electrochemical tests on the electrode made by such ultrathin sandwich nanosheets validate that the strategy is effective to obtain high performance electrodes for supercapacitors and lithium ion batteries. As an electrode of a lithium ion battery, it shows excellent cycling performance with a specific capacity close to 998 mA h g−1 at a current density of 0.1 A g−1; and as an electrode of a supercapacitor, capacitance retention of 87.6% is achieved over 2000 cycles at a constant current density of 20 A g−1.

This paper combines the dynamic complex network and DID (difference-in-differences) analysis to evaluate the effect of the negative list policy aimed at adjusting the sectoral structure of Shanghai. We construct a causal dynamic complex network based on the high frequency electricity consumption data of industrial and commercial firms to study the sectoral structure change and assess the impact of the negative list policy. Specifically, we use the negative list policy of industrial restructuring first implemented in Shanghai in 2014 to establish the DID model. The results show that the degree centrality, which reflects the importance of a sector in the sectoral structure, of these sectors regulated by the negative list policy is down 13.68 after June 2014, which is a percentage drop of 8.74%, and the other indicators of the complex network for the sectors treated by the policy are mostly decreasing. These results indicate that the policy definitely decreases the importance of sectors with more emissions and energy consumption, and the sectoral structure has been adjusted and upgraded in the direction of less energy consumption and less emissions. After introducing interaction items, assessing the impacts of other policies, changing the parameters of the network construction, and using a network processed by the PMFG (plane maximum filter graph) and other means to check the robustness of results, the negative effects are still statistically significant.

The damage of equipment manufactured with ferromagnetic materials in service can be effectively detected by Metal Magnetic Memory Testing (MMMT) technology, which has received extensive attention in various industry fields. The effect of stress or strain on Magnetic Flux Leakage (MFL) signals of ferromagnetic materials has been researched by many scholars for assessing stress concentration and fatigue damage. However, there is still a lack of research on the detection of stress corrosion damage of ferromagnetic materials by MMMT technology. In this paper, the electrochemical corrosion system was designed for corrosion experiments, and three different experiments were performed to study the effect of corrosion on MFL signals. The distribution of MFL signals on the surface of the specimen was investigated. The results indicated that both the normal component Hn and tangential component Ht of MFL signals presented different signal characteristics when the specimen was subjected to different working conditions. Finally, two characterization parameters, Sn and St, were defined to evaluate the corrosion degree of the specimen, and St is better. The direct dependence of corrosion depth on the parameter was developed and the average error rates between the predicted and measured values are 8.94% under the same working condition. Therefore, the expression can be used to evaluate the corrosion degree of the specimen quantitatively. The results are significant for detecting and assessing the corrosion defect of ferromagnetic materials.

The major scientific goals of the DArk Matter Particle Explorer (DAMPE) are to study cosmic-ray electrons (including positrons) and gamma rays from 5 GeV to 10 TeV and nuclei from Z = 1 to 26 up to 100 TeV. The deposited energy measured by the Bismuth Germanate Oxide (BGO) calorimeter of DAMPE is affected by fluorescence attenuation in BGO crystals that are 600 mm long. In this work, an in-orbit attenuation calibration method is reported, and energy correction of the sensitive detector unit of the BGO calorimeter is also presented.

Separation of vertical integrated electricity sector and removal of entry barriers for power generation investment were advocated by China's electricity market reform in 2002. While market competitions were expected to intensify along with the increasing number of power generators and diversified ownerships, two major interventions, namely Benchmark On-grid Price regulations by the government and peak-frequency regulations by the dispatching organization manipulated the market competition frequently. This paper analyzes the mechanism of how dual regulation of price and quantity affects the efficiency of power plants, and then advocates an improved stochastic frontier analysis to examine the efficiency distortion of various utilities due to the price and quantity regulation by employing a newly developed firm-level data sets of power generation plants with capacity above 6000 kw over 2007 to 2012 in China, this paper shows that price regulation led to a deterioration of efficiency performance caused by the exaggeration with the actual on-grid price from the optimal equilibrium price. Additionally, centrally dispatched power plants suffered from negative impact of quantity regulation on the transient efficiency. Besides, the interactive effect of price and quantity regulation indicates that price regulation has greater negative impact on the centrally dispatched power plants than the non-centrally dispatched ones. There is also difference between the power plants of sub-industries. The thermal power plants are significantly influenced by the price and quantity regulation, while the renewable power plants are less likely to be influenced.

Magnetic memory method (MMM) is a newly developed passive nondestructive testing method, mainly used to detect the ferromagnetic materials. Because of the faster testing speed and the more convenient testing equipment, MMM has attracted many scholars’ attention. This paper designed wide plate tensile specimens without and with a defect to study the influence of stress distributions on magnetic-flux-leakage (MFL) signals. The three-dimensional (3D) MFL signals on the specimen surface along the directions parallel (x-axis) and vertical (y-axis) to the loading direction were measured. Finite element method (FEM) simulation and digital image correlation (DIC) testing were performed as comparison. Then a theoretical model was applied in finite element method (FEM) software to calculate the MFL signals. The experimental results are essentially in agreement with the calculated results. It is shown that the MFL signals on the measuring lines both parallel and vertical to the loading direction are capable of describing the load magnitude and stress inhomogeneity. Besides, the MFL gradient is in agreement with the equivalent stress distribution along the loading direction. The magnitude of MFL gradient vector developed in this paper shows a good correlation with the equivalent stress distribution vertical to the loading direction. Finally, five characterization parameters were extracted to evaluate the stress inhomogeneity.

This paper proposes a restoration mechanism based on convolution neural network (CNN) for electronic camouflage audio. Since there are certain change rules in the process of converting original audio into electronic camouflage audio and audio is short-time stationary, convolution and nonlinear mapping are performed on the historical sampling acoustic information and restoring factors of the electronic camouflage audio. After companding transformation, the reduction audio is outputted. In the experiment, the voiceprint features comparison, LPC analysis and human ear identity judgement are made between restoring audio and original audio. The results show the validity of the proposed mechanism. It is of great theoretical and practical significance to the restoration of electronic camouflage audio in judicial expertise.

This paper proposed a novel treatment for stomatitis using microneedles-based patches. We purposed to test whether appropriate physical stimulation by microneedles has a promotion effect on the healing of stomatitis. At the present stage, we have made a modeling of stomatitis last for more than one week on the oral mucosa of Sprague-Dawly (SD) rats and recorded the spontaneous recovery process.

Passive infrared (PIR) sensors are the most popular deployed sensors in building lighting control for individual presence detection. However, PIR sensors are motion detectors in nature, responding only to incident radiation variation, which lead to false negative detections, inaccurate occupancy estimation, and uncomfortable lighting swings, short lifetime of the equipment, and waste of energy. In this study, a shutter driven by a Lavet motor PIR (LAMPIR) sensor is developed for presence detection for both stationary and moving occupants. Building off our previous work on chopped PIR (C-PIR) and rotationally-chopped PIR (Ro-PIR) sensors, Lavet motor, a single-phase electro-mechanical vibrator, is introduced, which has many advantages over traditional servo motors and stepper motors in terms of power consumption, size, weight and noise level. Driven by pulsed signal from a microcontroller unit (MCU), the electro-mechanical vibrator drives a semi-transparent long-wave infrared (LWIR) optical shutter to shutter the field of view (FOV) of a PIR sensor periodically. Output voltage generated by a LAMPIR senor for occupied and unoccupied scenarios can be monitored and analyzed to identify presence accurately. Parametric studies are conducted to find the optimal setting of driving signal frequency, shutter width and shuttering period. The LAMPIR sensor reaches an accuracy of 100% for detecting stationary occupants up to a range of 4.5 m and moving occupants up to a range of 10 m, which improves the detection range of both C-PIR and Ro-PIR sensors (4.0 m for stationary and 8.0 m for moving occupancy detection). LAMPIR has a FOV of 90° in horizontal and 100° in vertical, which is reasonable for most applications. For a 17-hour-long presence detection test, LAMPIR can reach an accuracy of 93.52% to classify unoccupied, stationary and moving occupant scenarios. More importantly, the average power consumption of LAMPIR is 0.19 W, which is 82% less than that of the C-PIR sensor and 89% less than that of the Ro-PIR sensor.

High-frequency and unit-level consumption data collected by smart meters makes accurate and short-term predictions of sectoral electricity demand possible. To facilitate electricity market pricing, load management and demand response, models handling such high-dimensional data-sets are expected to realize effective variable selection, accurate prediction and, in the meantime, retain the economic mechanisms as much as possible. This paper attempts to propose a complex network based on a variable selection model that retains the causality relationships among the most relevant sectors and can achieve prediction accuracy that is comparable to other data-driven models. A dataset containing 266,000 industrial and commercial firms in Shanghai is employed to develop a complex network relying on Granger causality and correlation coefficients. Dominant nodes are selected based on a Planar Maximally Filtered Graph algorithm and then serve as explanatory variables in the linear regression model. Further comparison with LASSO, PCA and Ridge regression shows that this model can successfully realize dimension reduction but maintain significant economic mechanisms, and achieving unbiased estimation and acceptable accuracy.

To manage the peak load by demand response, time-of-use (TOU) pricing with hourly and seasonal adjustments has been applied in industrial and commercial sectors in Shanghai. However, the requirement of continuous production and exogenous output level might be a serious barrier for responding to TOU price, as these are different across industrial sectors, firm scale or even seasons. Thus, the extent to which heterogeneous firms respond to price signals is still ambiguous and worthy of exploration. Based on a regression discontinuity approach, we disentangle the firm-level effects of TOU pricing for industrial and commercial firms. While the overall result shows a nonsignificant average response to TOU pricing, the firm-level analysis concerning individual heterogeneity indicates that smaller firms are much more sensitive to TOU pricing than larger firms. Moreover, this effect is much more significant in the commercial sector. This study expands understanding of the heterogeneous effects of TOU pricing with consideration of firm-level information and fills the gap between different estimation results from the previous literature. The results also indicate a price policy failure and unbalanced effects on industrial and commercial firms.

© 2017, Springer Science+Business Media, LLC. Online Value-at-Risk (VaR) analysis in high-dimensional space remains a challenge in the era of big data. In this paper, we propose an online sequential learning non-parametric VaR model called OS-GELM which is an autonomous cognitive system. This model uses a Generalized Autoregressive Conditional Heteroskedasticity (GARCH) process and an online sequential extreme learning machine (OS-ELM) to cognitively calculate VaR, which can be used for online risk analysis. The proposed model not only learns the data one-by-one or chunk-by-chunk but also calculates VaR in real time by extending OS-ELM from machine learning to the non-parametric GARCH process. The GARCH process is also extended to one-by-one and chunk-by-chunk mode. In OS-GELM, the parameters of hidden nodes are randomly selected. The output weights are analytically determined based on the sequentially arriving data. In addition, the generalization performance of the OS-GELM model attains a small training error and generates the smallest norm of weights. Experimentally obtained VaRs are compared with those given by GARCH-type models and conventional OS-ELM. The computational results demonstrate that the OS-GELM model obtains more accurate results and is better at forecasting the online VaR. OS-GELM model is an autonomous cognitive system to dynamically calculate Value-at-Risk, which can be used for online financial risk assessment about human being’s behavior. The OS-GELM model can calculate VaR in real time, which can be used as a tool for online risk management. OS-GELM can handle any bounded, non-constant, piecewise-continuous membership function to realize real-time VaR monitoring.

The constant elasticity of substitution (CES) function is an important function that is widely used in both theoretical analysis and applied economics. We propose a systematic framework to estimate the deep nested CES function using the nonlinear least squares (NLS) method. This method fills the gap between current empirical studies and large-scale applied economic models such as computable general equilibrium (CGE) models. We estimate the elasticities of substitution at both the regional and sectoral levels using this framework. The results indicate that some elasticities of substitution are larger than those in the existing literature. In addition, our results emphasize the heterogeneity of the elasticities of substitution across regions and sectors during application.

An effective approach to reduce tool wear remains a long-standing challenge in using diamond-cutting ferrous metals. To achieve this objective, we explored a new method of cold plasma and ultrasonic elliptical vibration-assisted diamond cutting. The method consisted of flexible cold plasma generator conveniently transferred cold plasma to the tool-workpiece interface, and an ultrasonic elliptical vibration precisely controlled system vibration characteristics. Molecular dynamics simulation was employed to study the graphitization process of Fe catalytic diamond. By diagnosing the active species of the plasma jet and analyzing the reaction process of plasma with fresh workpiece surface, we demonstrate the inhibition mechanism of nitrogen cold plasma to the diamond tool chemical wear. Intermittent cutting characteristics of ultrasonic elliptical vibration change the value and direction of the cutting force and are conducive to exclude chips. This feature therefore reduces the cutting temperature and then retards the graphitization process of the diamond. These results establish a new cutting technology that combines the advantages of vibration cutting and surface modification and provide a cutting medium that targets the effective reduction of tool wear for diamond-cutting ferrous metals.

Er3+/Ce3+ co-doped tellurite glasses with composition of TeO2-GeO2-Li2O-Nb2O5 were prepared using conventional melt-quenching technique for potential applications in Er3+-doped fiber amplifier (EDFA). The absorption spectra, up-conversion spectra and 1.53 µm band fluorescence spectra of glass samples were measured. It is shown that the 1.53 µm band fluorescence emission intensity of Er3+-doped tellurite glass fiber is improved obviously with the introduction of an appropriate amount of Ce3+, which is attributed to the energy transfer (ET) from Er3+ to Ce3+. Meanwhile, the 1.53 µm band optical signal amplification is simulated based on the rate and power propagation equations, and an increment in signal gain of about 2.4 dB at 1 532 nm in the Er3+/Ce3+ co-doped tellurite glass fiber is found. The maximum signal gain reaches 29.3 dB on a 50 cm-long fiber pumped at 980 nm with power of 100 mW. The results indicate that the prepared Er3+/Ce3+ co-doped tellurite glass is a good gain medium applied for 1.53 µm broadband and high-gain EDFA.

Silver nanoparticles (NPs) were embedded into Er 3+ /Yb 3+ codoped tellurite glasses prepared using melt-quenching and subsequent heat-treating techniques, and the influence of heat-treating temperature (300, 330, 360 and 390 °C) on the 1.53 µm fluorescence of Er 3+ under the excitation of 980 nm LD was investigated. The 1.53 µm fluorescence increased with the heat-treating temperature in the investigated temperature range, which is attributed to the enhanced local electric field around Er 3+ induced by localized surface Plasmon resonance (LSPR) effect of silver NPs. Transmission electron microscopy (TEM) images revealed that the low heat-treating temperature (300 °C) is not enough to nucleate and grow the silver NPs, while near-spherical silver NPs with mean diameter ~13 nm were dispersed in glass heat-treated for 6 h at temperature 390 °C. The results indicate that a relatively high heat-treating temperature is beneficial for the formation of silver NPs and in turn the enhancement of 1.53 µm fluorescence in Er 3+ /Yb 3+ codoped tellurite glass.

Tellurite glasses (TeO2–ZnO–La2O3) doped with Er3+, Er3+/Ce3+ and Er3+/Ce3+/Yb3+ have been prepared using the melt-quenching technique, and the absorption spectra, fluorescence and up-conversion emission spectra together with the differential scanning calorimeter (DSC) curves and X-ray diffraction (XRD) patterns were measured to evaluate the effects of Ce3+ and Yb3+ introduction on the 1.53 µm band spectroscopic properties of Er3+, thermal stability and structural nature of glass hosts. The Judd–Ofelt intensity parameters Ω t (t=2,4,6), spontaneous emission probabilities, radiative lifetimes and branching ratios of several Er3+ transitions were calculated from the measured absorption spectra based on the Judd–Ofelt theory. The co-doping with Ce3+ was effective on the suppression of up-conversion emission of Er3+ owing to the phonon-assisted energy transfer: Er3+:4I11/2+Ce3+:2F5/2→Er3+:4I13/2+Ce3+:2F7/2, while the co-doping with Yb3+ had the effect of obviously increasing the Er3+ population at 4I11/2 level via the resonant energy transfer: Yb3+:2F5/2+Er3+:4I15/2→Yb3+:2F7/2+Er3+:4I11/2, both of which contributed the effective enhancement of 1.53 µm fluorescence emission. The quantitative studies were carried out to elucidate the energy transfer mechanism by calculating the microscopic parameters and phonon contribution ratios. The glass transition temperature ( T g ), crystallization onset temperature ( T x ) and the difference Δ T ( = T x − T g ) , which characterize the thermal stability of glass host, increased with the Ce3+ and Yb3+ co-doping and for all glass samples the value of Δ T is larger than 145 °C. The glass structural nature was demonstrated from the measured XRD patterns with no sharp diffraction peaks. The results of the present work indicated that the prepared Er3+/Ce3+/Yb3+ co-doped tellurite glass is a potential material for developing broad-band and high-gain optical amplifiers and other optical devices.

The silver nanoparticles (Ag NPs) was introduced into Er3+/Ce3+ codoped tellurite glasses with composition of TeO2–ZnO–La2O3 and the effects of Ag NPs on the 1.53 μm band spectroscopic properties of Er3+ ions, structural nature and thermal stability of glass hosts were investigated. The absorption spectra, upconversion emission spectra, 1.53 μm band fluorescence spectra together with the X-ray diffraction (XRD) patterns, differential scanning calorimeter (DSC) curves and transmission electron microscopy (TEM) image were measured. It was found that the near-spherical shape Ag NPs with average diameter of about 19 nm dispersed uniformly in the glass matrix, and the Er3+/Ce3+ codoped tellurite glasses containing Ag NPs exhibited an obvious enhancement in the 1.53 μm band fluorescence, which is attributed to the intensified local electric field induced by Ag NPs and the possible energy transfer from Ag NPs to Er3+ ions. The enhanced effect of Ag NPs on the 1.53 μm band fluorescence was elucidated by the obtained large Judd–Ofelt intensity parameter Ω6 and the calculated quantum efficiency of Er3+:4I13/2 level. In addition, the thermal stability of prepared glass samples increased with the introduction of Ag NPs and the amorphous structural nature was demonstrated by the measured XRD patterns with no sharp diffraction peak. The present results indicate that the prepared Er3+/Ce3+ codoped tellurite glass with Ag NPs has good prospect as a gain medium applied for 1.53 μm band Er3+-doped fiber amplifiers (EDFAs).

New Ho 3+ /Yb 3+ codoped tellurite glasses (TeO 2 –Bi 2 O 3 –ZnO–Na 2 O) prepared by melt-quenching technique were investigated to realize visible-band upconversion emissions applied for compact fiber lasers. The absorption spectra, upconversion emission spectra, differential scanning calorimetry (DSC) curves, X-ray diffraction (XRD) and Raman spectra were measured to characterize the spectroscopic properties of Ho 3+ , thermal stability and structural nature of glass hosts. Under the excitation of 980 nm laser diode (LD), the intense green (∼543 nm) and red (∼657 nm) upconversion emissions corresponding to 5 F 4 ( 5 S 2 ) → 5 I 8 and 5 F 5 → 5 I 8 transitions of Ho 3+ respectively are simultaneously observed. The power dependence study of upconversion intensities on excited pump power revealed that the Ho 3+ population at 5 F 4 ( 5 S 2 ) and 5 F 5 levels was originated from two-photon absorption process based on the energy transfer from Yb 3+ to Ho 3+ . The energy transfer mechanism from Yb 3+ to Ho 3+ was investigated and relevant micro-parameters (energy transfer coefficient and critical radius) and phonon contribution ratio were presented. With the increase of Yb 3+ doped concentration, both the green and red upconversion intensities enhanced greatly, meanwhile the thermal stability of glass hosts, characterized by the three characteristic temperatures, also got a slight improvement. Furthermore, the glass structure was briefly analyzed with the calculated Judd–Ofelt intensity parameters, the measured Raman spectra and XRD curves. The present results indicate that the new synthesized Ho 3+ /Yb 3+ codoped tellurite glass with intense green and red upconversion emissions is a promising medium applied for the visible-band fiber lasers.

Nd3+ was introduced into Er3+ doped tellurite glass with composition of TeO2 Nb2O5 ZnO Na2O to improve the 2.7 μm band fluorescence upon the excitation of 800 nm LD. The DSC curve and Raman spectrum were measured to characterize the thermal stability and vibration nature of glass host. The absorption spectra, visible, near- and mid-infrared fluorescence emission spectra were measured to evaluate the effects of Nd3+ introduction on the spectroscopic properties especially the 2.7 μm band fluorescence of Er3+. It is shown that the prepared tellurite glass exhibits a large glass transition temperature and no obvious crystallization peak is observed in the measured temperature range of 200–550 °C. Moreover, the introduction of Nd3+ significantly improves the 2.7 μm band fluorescence intensity through joint energy transfer processes between the relevant excited levels of Er3+ and Nd3+, and the energy transfer mechanisms are further investigated in detail by calculating energy transfer micro-parameters and efficiency. The excellent thermal stability and strong 2.7 μm fluorescence emission aroused by adopting codoping scheme indicate that the prepared Er3+/Nd3+ codoped tellurite glass is a potential glass medium applied for the 2.7 μm mid-infrared band lasers.

Shanghai, as the most advanced mega city in China, has launched a pilot carbon emission trading scheme (SH-ETS) that is designed to achieve a compromise between the domestic context in Shanghai, and a need for national policy appeal. This paper gives an overview of the latest progress of the SH-ETS and sheds some light on the features of key design components, such as the threshold for inclusion, sector coverage, cap setting, allowance allocation and the Monitoring, Reporting and Verification (MRV) system. Based on a concern that manipulative principles and economic dynamics may lead to uncertainties and ultimately influence the emission reduction effect of the scheme, this paper conducts an evaluation of potential uncertainties, such as those caused by changes in patterns of economic growth, strategic trading activities related to the bankable allowances, carbon leakage risks and insufficient MRV capabilities. To advance the experiment to reality, this paper suggests some changes are made to the pilot, which include adjusting the allowance allocation principles to facilitate change in the domestic energy structure, improving the disclosure of emission data to guarantee information symmetry, gauging the carbon leakage risks to strengthen compliance, and introducing risk management for non-regulated players and derivatives products.

Thermal-sensitive electricity usage accounts for the majority of residential electricity use worldwide. Moreover, it has substantial impacts on the power system and the society during the extreme weathers. We propose a novel data-driven method to identify the thermal-sensitive electricity usage and quantify the associated thermal sensitivity directly from widely deployed smart meter data, where the Multivariate Adaptive Regression Splines model provides both the flexibility and interpretability. We apply the proposed method to analyze the thermal sensitivity of individual residential electricity use for two representative urban areas in the United States and China, San Francisco Bay Area and Shanghai, respectively. More than 120,000 households' smart meter data sampled from Bay Area and Shanghai is used for the analysis. To best of our knowledge, we for the first time reveal the heterogeneous patterns of thermal sensitivity of households from USA and China at the individual level. The difference of thermal sensitivity serves as an important factor for personalized techniques and policies towards mitigating the impact of extreme weathers to power systems and improving the buildings' energy efficiency.

A droplet-born air-blowing method is an advanced method of the drawing lithography enables simple and fast fabrication, which does not require UV irradiation or moulding process. However, it has disadvantages such as low throughput in the formation of droplet array as it uses the dispenser to make droplets one by one. To increase the throughput while also simplifying the fabrication method, we suggest a novel fabrication method for microneedles array (MNs array) using the shadow mask, which can fabricate the microneedles array uniformly. Furthermore, our method enables us to control the amount of polymer in the microneedle by adjusting the hole dimension as well as the thickness of the shadow mask. Here, we established the use of a shadow mask to form multiple droplet array at one time and then achieved microneedles array from the droplet array by drawing lithography in a short time (≤ 10 min). We anticipate that shadow mask assisted drawing lithography will be suitable to improve the fabrication throughput of dissoluble microneedle for new generation of drug delivery system.

Ultrathin dual phase nanosheets consisting of alternating spinel Li

Let $D_{k}$ be a set with $k$ distinct elements of integers such that $d_{1}, Comment: Some small revise

This paper proposes a fixed price auction mechanism to overcome asymmetric information problem considering firms with heterogeneous emission abatement costs. When facing fixed price permit auction and emission trading market, firms will make trade-offs between buying permits at fixed price and buying permits from markets. Equilibrium results show that firms have enough incentives to tell the truth about their private emission cost information. The numerical simulation uses China’s real data to compare performances of fixed price auction scheme to pure price scheme and pure quantity scheme. Simulation results are consistent to theoretical predictions and fixed price auction scheme performs best among three schemes. This result gives quite important implication for China to build its national emission trading scheme.

When there exist uncertainties, different carbon pricing mechanisms usually lead to different results. Some sectors will suffer more in the presence of uncertainties while other sectors suffer less. Thus choosing appropriate sectors to impose low carbon policy would be quite important in order to avoid worse economic outcome. We propose a new indicator which is called “optimal return rate” to facilitate determining the sector coverage. The sector with a low optimal return rate should be given high priority to be imposed low carbon policy and vice versa. We also conduct a numerical simulation using China’s real data to calculate optimal return rates of China’s sectors. Simulation results show that most energy-intensive sectors have quite low optimal return rates and should be first included in either emission trading scheme or carbon tax scheme. Moreover, sectors included in the first stage of building China’s national carbon emission trading scheme are also in accordance with our simulation results. This means the new indicator has great power in guidance of building China’s national carbon emission trading scheme in the future.

A long, quasi-homogeneous cold plasma jet was generated through a homemade cold plasma jet generating device. Friction-wear test and assisted cutting of Ti6Al4V were studied under air, nitrogen, and nitrogen cold plasma jet (NPJ) atmospheres. The friction coefficient under nitrogen jet was small, and the wear appearance was smooth at low-speed friction. At high-speed friction, the friction coefficient under NPJ was the smallest, which declined by 70 % compared with that under air atmosphere. The scratches and adhesive traces on the friction surface were the lightest as well. The lubrication and cooling effects were not evident under low-speed cutting, whereas the NPJ enabled the radial force Fy and the average flank wear width VB to decrease by nearly 40–47 % respectively under high-speed cutting compared with the ones under air atmosphere. Results show that the NPJ assisted cutting has little influence on the surface roughness, residual stress, and work hardening of workpieces, while the machinability of Ti6Al4V can be effectively improved.

A novel Er3+, Tm3+ and Yb3+ codoped tellurite glasses with composition of TeO2–Bi2O3–ZnO–Na2O was prepared by conventional melt-quenching technique to realize the multicolor upconversion (UC) emissions. The absorption spectrum, UC emission spectrum, Raman spectrum, X-ray diffraction (XRD) and differential scanning calorimeter (DSC) curves were measured to characterize the prepared glass samples. Under the excitation of 980 nm laser diode (LD), bright multicolor luminescence composed of red, green and/or blue UC emissions corresponding to the transitions 4F9/2→4I15/2, 2H11/2(4S3/2)→4I15/2 of Er3+ and 1G4→3H6 of Tm3+ were observed in the Er3+/Yb3+, Tm3+/Yb3+ and Er3+/Tm3+/Yb3+ codoped glass samples, which were mainly attributed to the successive energy transfers from Yb3+ to Er3+ and Tm3+, respectively. The energy transfer mechanisms from the Yb3+:2F5/2 level to Er3+:4I11/2 and Tm3+:3H5 levels were further investigated by quantitatively calculating the energy transfer micro-parameters and phonon contribution ratios. Meanwhile, the difference ( Δ T = T x − T g ) between the glass crystallization onset temperature (Tx) and the transition temperature (Tg) which increase slightly with rare-earth (RE) doped concentration, was larger than 140 °C for all glass samples. Furthermore, the amorphous nature of glass structure was demonstrated by the measured XRD curves. The excellent thermal stability and multicolor luminescent characteristic indicate that the present investigated Er3+/Tm3+/Yb3+ codoped tellurite glasses could be used in the fields of solid state multicolor displays and other luminescent devices.

Ho3 +/Yb3 + codoped zinc-tellurite glasses containing silver nanoparticles (NPs) were prepared using the conventional melt-quenching technique. The detailed effect of silver NPs on the upconversion emission of Ho3 +, thermal stability and structure behavior of glass hosts was investigated from the measured absorption spectra, upconversion emission spectra, differential scanning calorimeter (DSC) curves, X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images. Two frequency upconversion emission bands centered at 546 nm (green) and 657 nm (red) corresponding to Ho3 + transitions of 5F4(5S2) → 5I8 and 5F5 → 5I8, respectively, are simultaneously observed under the 980 nm excitation at room temperature. It is shown that the introduction of silver NPs can further improve the upconversion emissions of Ho 3 + and thermal stability of glass host, while the glass structure maintains the amorphous nature. The enhanced upconversion emission is mainly attributed to the increased local electric field around Ho 3 + induced by localized surface plasmon resonance (LSPR) effect of silver NPs. Furthermore, the energy transfer (ET) mechanism from Yb3 +:2F5/2 level to Ho3 +:5I6 level is quantitatively analyzed by calculating relevant micro- parameters and phonon contribution ratio.

Tm 3+ , Ho 3+ and Yb 3+ codoped tellurite glasses (TeO 2 Bi 2 O 3 ZnO Na 2 O) were prepared using conventional melt-quenching technique to realize the sensitized near-infrared to visible multicolor upconversion emission. The X-ray diffraction (XRD) curves, Raman spectra, differential scanning calorimeter (DSC) curves, absorption spectra and visible upconversion emission spectra were measured to characterize the structure nature, thermal stability and upconversion spectroscopic properties of rare earth (RE) codoped glass samples. Upon the excitation of 980 nm laser diode (LD), the multicolor upconversion emissions were experimentally observed from the prepared glass samples owing to the intense blue (∼477 nm) upconversion fluorescence of Tm 3+ and green (∼544 nm) and red (∼657 nm) upconversion emissions of Ho 3+ , which have been attributed to the result of the multi-step energy transfer (ET) from Yb 3+ to Tm 3+ (and Ho 3+ ) and excited state absorption (ESA). The ET mechanism between Yb 3+ : 2 F 5/2 and Tm 3+ : 3 H 5 (and Ho 3+ : 5 I 6 ) levels were further investigated by calculating the micro-parameters (energy transfer coefficient C DA and critical radius R C ). In addition, the glass transition temperature ( T g ) increases with the RE doped concentration and the estimated difference (Δ T ) between the onset crystallization temperature ( T x ) and the glass transition temperature ( T g ) for all glass samples is larger than 140 °C, while the glass structure maintains the amorphous nature. The excellent thermal stability and multicolor emission characteristics with RE doped concentration indicate that the studied Tm 3+ /Ho 3+ /Yb 3+ codoped tellurite glasses could be used in the fields of solid state multicolor displays and illumination devices.

China is experiencing intensified industrialisation and motorisation. In the world׳s largest emerging economy, energy efficiency is expected to play a critical role in the ever-rising demand for energy. Based on factual overviews and numerical analysis, this article carries out an in-depth investigation into the effectiveness of policies announced or implemented in recent decades targeted at energy conservation in the energy intensive manufacturing and transportation sectors. It highlights nine energy intensive sectors that achieved major improvements in their energy technology efficiency efforts. Under the umbrella of the 11th Five-Year Plan, these sectors׳ performances reflect the effectiveness of China׳s energy conservation governance. Numerous actions have been taken in China to reduce the road transport sector׳s demand for energy and its GHG emissions by implementing fuel economy standards, promoting advanced energy efficient vehicles, and alternative fuels. Coal-based energy saving technologies, especially industrial furnace technologies, are critical for China׳s near and medium-term energy saving. In the long run, renewable energy development and expanding the railway transport system are the most effective ways to reduce energy use and GHG emissions in China. Fuel economy standards could reduce oil consumption and GHGs by 34–35 per cent.

The silver nanoparticles (NPs) was introduced into the Er 3+ /Yb 3+ codoped tellurite glasses with composition of TeO 2 –ZnO to improve the 1.53 µm band fluorescence of Er 3+ and the thermal stability of glass host. The UV–Vis–NIR absorption spectra, 1.53 µm band fluorescence spectra and fluorescence decaying curves, the differential scanning calorimeter (DSC) curves, X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) images of glass samples were characterized to investigate the effect of silver NPs on the fluorescence properties of Er 3+ , thermal stability and structure behavior of glass host. It is shown that the Er 3+ /Yb 3+ codoped tellurite glass emits intense 1.53 µm band fluorescence with peak wavelength located at about 1532 nm under the 980 nm excitation. The introduction of silver NPs further improves the fluorescence intensity of Er 3+ which is attributed to the enhanced local electric field effect induced by localized surface Plasmon resonance (LSPR) of silver NPs and the possible energy transfer from silver NPs to Er 3+ . An improvement by about 62% of 1.5 3 µm band fluorescence intensity was found in the studied Er 3+ /Yb 3+ codoped tellurite glass containing 0.5 mol% amount of AgNO 3 . In addition, the thermal stability of glass host increases with the introduction of silver NPs while the glass structure maintains the amorphous nature. The present results indicate that the prepared Er 3+ /Yb 3+ codoped tellurite glass with an appropriate amount of silver NPs has good prospect as a gain medium applied for 1.53 µm band broad and high-gain erbium-doped fiber amplifiers (EDFAs).

A model of Er3+-doped chalcogenide glass (Ga5Ge20Sb10S65) microstructured optical fiber (MOF) amplifier under the excitation of 980 nm is presented to demonstrate the feasibility of it applied for 1.53 μm band optical communications. By solving the Er3+ population rate equations and light power propagation equations, the amplifying performance of 1.53 μm band signals for Er3+-doped chalcogenide glass MOF amplifier is investigated theoretically. The results show that the Er3+-doped chalcogenide glass MOF exhibits a high signal gain and broad gain spectrum, and its maximum gain for small-signal input (−40 dBm) exceeds 22 dB on the 300 cm MOF under the excitation of 200 mW pump power. Moreover, the relations of 1.53 μm signal gain with fiber length, input signal power and pump power are analyzed. The results indicate that the Er3+-doped Ga5Ge20Sb10S65 MOF is a promising gain medium which can be applied to broadband amplifiers operating in the third communication window.

As the atomic force microscope (AFM) becomes a more accessible tool in the laboratory, researchers involved in the development of pharmaceutical formulations are taking advantage of its unique capabilities. In this work we review the uses of the AFM in the development of hydrofluoroalkane-based pressurized metered-dose inhaler formulations. Perspectives and limitations of the AFM and related techniques in this area also discussed.

Magnetization and magnetostriction are of critical importance to understand the magnetic behavior of ferromagnetic materials under stress and magnetic fields. The micromechanism of magnetization (or magnetostriction) is determined by the probability of angular distribution of magnetic moments and saturation magnetization (or saturation deformation). Thus, the probability of angular distribution of magnetic moments is important to construct the relationship between the magnetization (or magnetostriction) and magnetic moments. In this letter, a new microstatistical model is developed to explain the magnetization and magnetostriction mechanisms for isotropic materials. The probability of angular distribution between magnetic moment and magnetic field is expressed by a modified Boltzmann distribution. The results calculated by the present model are compared with the experimental results. The values of the determination coefficient R 2 indicate that the present model can accurately describe the relationship between magnetization and magnetostriction under both stress and magnetic fields.

A certain amount of WO3 oxide was introduced into the Ho3+/Tm3+ codoped tellurite glass, and the absorption spectra, fluorescence spectra, Raman spectra, X-ray diffraction patterns and differential scanning calorimeter curves were measured to illustrate the enhanced effects of WO3 on the 2 µm fluorescence of Ho3+ and thermal stability of glass host. Under the excitation of 808 nm LD, the 2 µm fluorescence of Ho3+ increases obviously with the partial substitution of TeO2 by WO3 oxide, which is attributed to the enhanced energy transfer process from Tm3+:3F4 to Ho3+:5I7 level by providing a relatively large phonon energy. Meanwhile, the thermal stability of glass host increases accordingly, which is mainly attributed to the formation of thermal stability W=O bond. The intense 2 µm fluorescence together with good thermal stability indicates that Ho3+/Tm3+ codoped WO3 modified tellurite glass is a potential laser glass for efficient 2 µm emission.