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Two commonly observed charge transport mechanisms in single-molecule junctions are coherent tunneling and incoherent hopping. It has been generally believed that tunneling processes yield temperature-independent conductance behavior and hopping processes exhibit increasing conductance with increasing temperature. However, it has recently been proposed that tunneling can also yield temperature-dependent transport due to the thermal broadening of the Fermi energy of the contacts. In this work, we examine a series of rigid, planar furan oligomers that are free from a rotational internal degree of freedom to examine the temperature dependence of tunneling transport directly over a wide temperature range (78-300 K). Our results demonstrate conductance transition from a temperature-independent regime to a temperature-dependent regime. By examining various hopping and tunneling models and the correlation between the temperature dependence of conductance and molecular orbital energy offset from the Fermi level, we conclude thermally assisted tunneling is the dominant cause for the onset of temperature-dependent conductance in these systems.

Zeng-Bing Liu,1 Qiang Li,1 Wen-Xia Liu,1 Xin-Hai Li,1 Kai Ma,1 Yu-Bao Huo,1 Jin-Guang Wang,1 Qing-He Wang,1 Ya-Dong Yu2 1Department of Hand and Foot Surgeries, The No. 4 People’s Hospital of Hengshui, Hengshui, 053000, People’s Republic of China; 2Department of Hand Surgeries, The Third Hospital of Hebei Medical University, Shijiazhuang, 050000, People’s Republic of ChinaCorrespondence: Zeng-Bing Liu, Department of Hand and Foot Surgeries, The No. 4 People’s Hospital of Hengshui, No. 485 of Xinhua West Road, Taocheng District, Hengshui, 053000, People’s Republic of China, Tel +86 318 2173010, Email drliuzbhfs@outlook.comObjective: The present study aims to explore the (1) clinical effects of the modified Masquelet technique, whose improved Masquelet technique innovates the in vitro plasticity of the bone cement module and prefabricated hollow design, and the Kirschner wire external fixation-assisted autologous bone transplantation technique in the treatment of segmental metacarpophalangeal bone defects and (2) the differences between the two techniques.Methods: The clinical data of 32 patients with segmental metacarpophalangeal bone defects (15 patients treated with the modified Masquelet technique and 17 patients treated with the self-made Kirschner wire external fixation technique) admitted to our department between January 2012 and January 2020 were retrospectively analyzed. The postoperative bone healing time, hand function, and complications were compared between the two groups.Results: The two groups were comparable; there were no significant differences in age, sex, length of bone defect, and time from injury to operation between the two groups (P > 0.05). All patients were followed up with for 6– 24 months (average = 13.7 months), and all patients with segmental metacarpophalangeal bone defects achieved fracture healing. The postoperative hospital stay, fracture healing time, functionary scores of the affected limb, and incidence of severe complications were better in the modified group than in the external fixation group (P < 0.05).Conclusion: Compared with the Kirschner wire external fixation stent assisted autologous bone transplantation, the improved Masquelet technique has the advantages of simple operation, fast healing, accurate effect, wide indications, and less complications, making it more worthy of clinical promotion.Keywords: segmental metacarpophalangeal bone defect, modified, Masquelet technique, curative effect

A series of biruthenium complexes linked by oligothiophene bridges of variable lengths (4a–4d) have been prepared to probe intramolecular electronic delocalization as a function of the chain length...

Ecological green has become the basic national policy in China. Green buildings are springing up in large numbers, but there are few corresponding solutions. In view of the characteristics of various complex data produced by the green building complex with many business forms and green technologies, and the difficulty of unified management and control, this paper proposes to establish a two-level distributed database to deal with the heterogeneous data and adopt the method of service data object-based middleware and data warehouse to deal with the data. According to the response requirements and data requirements of different functions of the platform, data fusion is performed in different ways. Query speed of data is optimized. And then reach the unified management of green building complex.

Ferula ferulaeoides (Steud.) Korov. is a perennial herb that belongs to Umbelliferae (Apiaceae). Its resin and roots have extensive commercial and medicinal value in the Xinjiang region. However, the resin-secreting resin ducts (RDs) of F. ferulaeoides have not been studied in detail. This study used optical and transmission electron microscopy to explore the anatomical features, including the distribution, size, and structure, of the RDs among different organs of F. ferulaeoides. The microstructure data revealed that the RDs consisted of a round lumen, a layer of secretory cells, and multiple layers of sheath cells. Notably, the RDs in stem were arranged alternatively in a multilayered ring with vascular bundles of three distinct sizes. The ultrastructural analysis revealed that organelles in the secretory cells potentially play important roles in resin secretion. Those data may be of great significance to understanding the anatomy of the RDs in Ferula L. and Umbelliferae.

An homologous series of divinylchalcogenophene-bridged binuclear ruthenium complexes [(PMe3)3Cl(CO)Ru]2(μ-CH=CHC4H2XCH=CH) (4a-4d, X = O, S, Se, Te) has been synthesized and fully characterized by X-ray crystallography and various spectroscopic techniques. Single-crystal X-ray diffraction results show a distinct short-long bond length alternation along the polyene-like hydrocarbon backbone, with the geometric constraints imposed by the chalcogenophene leading to an increasing distance between two metal centres (dRu-Ru) in complexes 4a-4d as the heteroatom in the five-membered ring is changed from oxygen (9.980 A in 4a) to tellurium (11.063 A in 4d). The complexes undergo two sequential one-electron oxidation processes, the half-wave potential and separation of which appear to be sensitive to a range of factors including aromatic stabilization and reorganization energies. Analysis of [4a-4d]n+ (n = 0, 1, 2) by UV-Vis-NIR and IR spectroelectrochemical methods, supported by DFT calculations (n = 0, 1) revealed that the redox character of the complexes is dominated by the polyene-like backbone, with the chalcogenide playing a subtle but influential, structural rather than electronic, role. In the radical cations [4a-4d]+, charge is rather effectively delocalized over the 10-atom Ru-{4-s-cis-all-trans-(CH=CH)4}-Ru chain, giving rise to a species with spectroscopic properties not dissimilar to oxidized polyaceylene.

The heterobinuclear complex OsCl2(PPh3)2[CHC(PPh3)CFcO] (Fc = (C5H4)Fe(C5H5)) (1) in which the two metal centers were connected by the skeleton of the osmafuran and cyclopentadienyl was synthesized via a one-pot reaction of OsCl2(PPh3)3 and FcCOCCH in high yield. Three derivatives (Os(η2-OCOO)(PPh3)2[CHC(PPh3)CFcO] (2), Os(NCS)2(PPh3)2[CHC(PPh3)CFcO] (3), and OsCl2(dppb)[CHC(PPh3)CFcO] (dppb = Ph2P(CH2)4PPh2) (4)) were obtained by the ligand substitution reactions of complex 1 with different reagents (Cs2CO3 (2), NaSCN (3) and dppb (4)), respectively. All of these complexes were characterized by NMR spectroscopy and elemental analysis and the structures of complexes 1, 3 and 4 were further confirmed by single crystal X-ray diffraction. Their electrochemical properties were studied by cyclic voltammetry and square wave voltammetry. The first redox wave was ascribed to the couple Os(II)/Os(III). All of these complexes exhibit two redox processes with a large peak separation. However, UV-Vis-NIR combined with theoretical calculation clearly indicated that (1) the Os center plays a major role in the one-electron oxidation process of heterobinuclear complexes 1–4 and the osmafuran could be better described as a carbene ligand; (2) the electronic communication between the Os and Fe center is absent, and the osmafuran with the electron-withdrawing phosphonium substituent actually functioned as an insulating bridge.

Specifying technical features of all kinds of distributed energy resources in operation control is the foundation of deploying active distribution network. This paper analyzes the technical characteristics of various distributed energy resources (DER) including micro-turbines, wind turbines, photovoltaic generations, distributed energy storage devices and flexible loads (FL), and discusses the demand response (DR) mechanisms and controllability of FL profoundly. Furthermore, on the basis of the economy and the reliability of the overall system, the in-depth study of active distribution network (ADN) typical integration modes which adapt to a low-carbon environment are carried out.

Wave gliders as innovative autonomous ocean-going vehicles harvest the abundant marine natural energy for persistent ocean environment monitoring. This paper analyzes wave glider’s operating mechanism and builds the dynamic model of wave glider. By simplifying the model into 3 DOS in longitudinal plane and selecting three generalized velocity, the kinematic equations and the generalized force can be confirmed. Then, based on the equation of Kane vector operation modeling method, the explicit kinetic model of wave glider is presented. According to simulation study of the kinetic model, the relationship between the motion state of wave glider and the wave motion are indicated. The study provides theoretical guidance and reference for wave glider design.

This paper has discussed the treatment of uncertainty in the market environment, using chance-constrained programming to describe the risk and Monte Carlo simulation method to calculate the risk factor, the risk factor is bound to establish transmission network flexible planning model, the result is a transmission planning of minimum comprehensive cost under uncertain environment for the future program.

This paper focused on power system security problems and proposed risk assessment and preventive control method of electric power system based on voltage risk. The method built up a system voltage risk indicators, and have system voltage risk identified through risk assessment, on this basis, reduced the risk of the system voltage by optimizing the control variables of the system, which of course can increase system security. Finally, Refers to a 5-node tests as examples to verify availability of this method.

Under the situation of distribution network construction, evaluating the reliability and comprehensive level of distribution network planning accurately is an important issue in decision-making progress. Based on the analysis of reliability related factors and the inner mechanism of the evaluation process, a reliability-based evaluation methodology of distribution network planning is proposed. Firstly, starting from the study of the reliability and conventional evaluation, a reliability-based index system and its evaluation process are presented. Then, combining the advantage of analytic hierarchy process (AHP) and date envelopment analysis (DEA) as well as Cross-Evaluation, a CE-DEA model with AHP constraint cone is developed for the comprehensive evaluating of distribution network planning scheme. Finally, the simulation results of a factual case are presented and discussed. The proposed methodology and comprehensive evaluation model are illustrated to be effective, providing useful guidance for the distribution network planning.

With the background of large-scale wind power integration grid, in order to reduce wind farm voltage fluctuation and the grid loss, through the scenario analysis method, the objective function model was established to determine the best SVCs compensation capacity and compensation point. Firstly, the initial operation states of the wind power systems were obtained by the Monte Carlo sampling and power flow was calculated to get the reactive power compensation point and its capacity. Then the result of optimization model was calculated by the improved genetic algorithm. IEEE 30 system was taken as an example for the simulation calculation and the calculation results verify the validity of the model.

Compared with other traditional energy, the small-scale hydropower which is intermittent energy can not be stored and scheduled. The greater fluctuant of the output power of small-scale hydropower leads to great difficult to the operation of the power system. Most of the existing small-scale hydropower forecasting is considered as the load forecasting factors, and there is not effective forecasting method. This paper establishes an output power forecasting model of the small-scale hydropower based on Projection Pursuit. The simulation results show that the new algorithm has a strong practical application in the small-scale hydropower output power forecasting and the forecast accuracy meets the scheduling requirements.

This paper elaborates the effect of wind speed on the output power of the wind farms at different locations. It also describes the correction of the power curve and shows the comparison chart of the standard power curve and the power curve after correction. In China's inland areas, wind farms altitude are generally higher, the air density is much different from the standard air density. The effect of air density on wind power output must be considered during the wind farm design.

Considering the randomness of wind speed and wind direction, the partial wake effect between wind turbines (WTs) in complex terrain was analyzed and a multiple wake model in complex terrain was established. Taking the power output characteristic of WT into consideration, a wind farm reliability model which considered the outages of connection cables was presented. The model is implemented in MATLAB using sequential Monte Carlo simulation and the results show that this model corrects the power output of wind farm, while improving the accuracy of wind farm reliability model.

This paper describe an approach to optimize the economy of electric vehicles’fast charging station investment with service satisfaction be constraints. An optimized model is proposed to study the relationship between the number of charge devices and economy of investment, which is based on the internal rate of return. Some service index like the queuing time and queuing length based on queuing theory are calculated to make sure the result reasonable and attainable for both investors and customers. At last, an example based on a conventional traffic flow and service intensity is simulated on Matlab to prove the effectiveness of the model.

In power system planning and operation, accurate assessment of overhead lines outage rate is essential for making timely decisions. The overhead lines are often influenced by many random events, such as accidents and weather conditions, resulting in power outages. Especially, the reliability of the overhead lines is subjected to weather conditions to a great extent[9]. At present, research about weather conditions dependent reliability is abundant, but many of them are based on synthetical weather, little of them base on specific weather conditions such as typhoon and thunder .This paper proposed outage model of overhead lines dependent upon typhoon an thunder. In power system planning and operation, accurate assessment of failure rate is essential for making informed decisions, The outage model proposed in this paper has significant meaning for the research of risk assessment of power systems.

A newly constrained multi-objective differential evolution optimization technique (CMODE) for security constrained economic/environmental dispatch (EED) was proposed. The proposed CMODE evolved a constrained multi-objective version of differential evolution (DE) by employing the traditional multi-objective differential evolution (DEMO) and constrain handle technique to balance the search between feasible region and infeasible region. The proposed CMODE method had been applied to solve the security constrained EED problem. Experiments had been carried on a standard test system. The results demonstrate the high efficiency of the proposed method to solve security constrained EED problem, and the necessary of taking security constrains into consideration.

This paper has proposed a wind farm generation output forecasting model based on projection pursuit (PP) and back propagation neural network (BPNN), in order to eliminate the influence of the bad points and mutations on and enhance robustness of the forecasting model. A median absolute deviation is used as projection index function, effectively avoiding the influence of the outlier. Firstly, Extract the principal components of each factor by PP. Then, input the principal components to the BPNN for training the network. Finally, forecast the wind farm generation output via the trained network. The simulation shows that the proposed approach is of higher accuracy.

It is the foundation for evaluating the reliability of transmission lines to obtain and analyze the original reliability parameters. However, these parameters depend on long- term statistic and calculation. In the case of lacking such parameters in a new project , this paper proposes a method of Principal Component Analysis to obtain the principal component of the impacting factors ,in which various factors affecting reliability parameters are taken into account. Through this method, we can use PCR to obtain the failure rate of the unknown transmission lines on the base of the known credible lines’ rates. The simulation results show that the proposed approach possesses higher forecasting accuracy and provides references for the power system dispatching departments and transmission lines maintenance departments.

As an important infrastructure of electric vehicles (EVs), EV fast charging station is of great significance in the popularization and development of EVs. Through the analysis of the characteristics of EV’s arriving time and charging duration in fast charging station, the stochastic service system was introduced and the queuing system model based on queuing theory was established. By calculating the indexes of the queuing system model, the desire model was used to optimize the number of EV chargers, which could save customers’ waiting time and reduce the investment of charging station. Finally, an example was simulated and calculated with MATLAB used as a simulation tool to verify the effectiveness of this approach.

Ammonia sulfite pulping liquor of wheat straw was treated by ultrafiltration. Experimental results indicated that the membrane with a cut-off of 10kDa was suitable for concentrating wheat straw liquor and had good anti-fouling property against pulping liquor. Permeability of ash turn higher with the increasing of volume reduction at the operating condition of 200 kPa and 25°C, and retentate was concentrated when volume reduced. Influences of ultrafiltration on physical properties of ammonia sulfite pulping liquor and its retentate after ultrafiltration were studied. Results showed that retentate had better performances as surfactant, concrete additive and dispersant. Surface tension of 1% lignin solution of retentate was 54.7 mN/m, which was lower than that of the untreated original lignosulfonate by 2.2 mN/m. Dispersing effect of retentate on cement was also investigated, it was found that flowability of neat cement paste improved from 70mm to 102mm.

Lignin-urea-formaldehyde resin adhesive was synthesized with alkali lignin from gramineae waste pulping liquor. Alkali lignin was purified and hydroxymethylated with HCHO and then crosslinked with urea-formaldehyde resin, polyvinyl alcohol and melamine. Results showed that lignin content in purified alkali lignin was 86.91%, both binding strength and free HCHO content of urea-formaldehyde resin synthesized from hydroxymethylated lignin reached the optimum value. The proper lignin amount for preparing resin was 30%, and the binding strength at this condition was 4.56MPa, and free formaldehyde content was 0.049%.

Liquid mulching film was prepared with technical gramineae lignin from waste pulping liquid via hydroxymethylation and then cross-linking reaction with urea or aromatic ring of lignin. Results showed the amount of lignin added had an influence on the property, viscosity and water resistance of liquid film material. This influence was little when lignin dosage was less than 30%, but turned apparent when lignin dosage was higher than 30%. The optimum lignin quantity was 30%. The growth of plant was accelerated when the concentration of liquid film material was around 1000 mg/L. Both planstic and liquid mulching film could improve soil temperature, the result of liquid film was a little worse than that of plastic film, but was better than the control. The optimum lignin dosage was 30% which had the best heat incubation effect.

Bamboo lignosulfonate was modified under the role of H2O2 and catalyst in order to improve the dispersing property of lignosulfonate. Results show that the amount of H2O2 and pH value have strong influences on characteristics of lignosulfonate. Cement paste fluidity of lignosulfonate modified at pH5 and 11% H2O2 is 178mm, which is 68% higher than that of unmodified lignosulfonate. Both of oxidative degradation and condensation occur during catalytic oxidation reaction, but oxidation is the main reaction when high amount of H2O2 is applied. The structure of lignosulfonate has some relationship to water reducing property. High molecular weight, high carboxylic content and proper sulfonic group content are the main reasons that enhance water reducing property of lignosulfonate.

Xylitol residue from corn cob was modified by alkaline sulfonation to produce lignosulfonate with good properties for concrete water reducing agent. Results showed that the optimum condition for lignin sulfonation was: total alkaline charge (calculated by Na2O) 16%, cooking temperature 170°C, holding time 3h, degree of sulfitation 80%. The yield of lignosulfonate at this condition was 68.1%. The fluidity of cement paste could reach 124mm when lignosulfonate dosage was 0.35% (on the base of solids). The surface tension of 1% lignosulfonate solution was 46.1 mN/m, and the content of sulfonic group was 2.16 mmol/g.

This article describes an information management system for the design of equipment and carried out in the power state companies. From software design to software development, and ultimately the results of completion,this system is of integration of today's most advanced technology RFID, with a three-dimensional structure, the use of personnel to operate on it. The system has the quick search features such as faults and statistics, this can shorten the time for fault location, greatly improved work efficiency.

Various negatively charged and positively charged inorganic nano-materials have been suggested to constitute the so-called microparticle retention systems with cationic or anionic polymers. Anionic microparticle retention systems consisted of cationic polymers and negatively charged inorganic nano-materials with various aspect ratios were reviewed while their working mechanism were analyzed. Cationic microparticle retention systems made up of either naturally or organo-modified cationic nano-materials were introduced.

The isotherm, mechanism and kinetics of carbon tetrachloride (CT) adsorption by polyacrylonitrile-based activated carbon fiber (PAN-ACF) were investigated in batch reactors and a continuous flow reactor, and the regeneration of PAN-ACF was also studied. Freundlich and Dubinin-Radushkevich (D-R) adsorption equations can well describe the adsorption isotherm. CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion. The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model, and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model. The ACF can be recycled through thermal regeneration, whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration. 78%–94% of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale, which confirms the efficacy of ACF under industrial conditions. The results indicate that PAN-ACF is applicable to CT removal from wastewater.

A series of neutral N-(substituted-benzamido)-N'-phenylthioureas (substituent = p-OC(2)H(5), p-CH(3), m-CH(3), H, p-Cl, p-Br, m-Cl, and p-NO(2)) were designed as anion receptors, in which the thiourea binding site was attached to the benzamido moiety via an N-N bond. The absorption spectra of these N-benzamidothioureas in acetonitrile peaked at ca. 270 nm were found to show unprecedented red shifts by 7 373 to 14 325 cm(-1) in the presence of anions such as AcO(-), F(-), and H(2)PO(4)(-). Under the same conditions, the classic neutral thiourea receptors, N-(substituted-phenyl)-N'-phenylthioureas, showed absorption spectral shifts in most cases of less than 800 cm(-1) with one exception of 6501 cm(-1). Control experiments, effects of protic solvent, and (1)H NMR titration confirmed the formation of hydrogen-bonding complexes between the new N-benzamidothiourea receptors and anions. The binding constants with AcO(-), for example, are at 10(5)-10(7) mol(-1) L order of magnitude, which are 13 to 590 times those of the corresponding classic N-phenylthioureas in the same solvent. It was found that, whereas the absorption of the N-benzamidothiourea receptors showed essentially no dependence on the substituent, the substantially red-shifted new absorption band of the N-benzamidothiourea-anion binding complex was sensitively subject to the substituent. A linear relationship was found between the absorption energies of the N-benzamidothiourea-acetate binding complexes and the Hammett constants of the substituents with a negative slope of -0.34 eV. This led to the assignment that the substantially red-shifted absorption band was the ground-state intramolecular charge-transfer absorption with the substituent locating in the electron acceptor moiety. It was concluded that anion binding to the thiourea moiety of the N-benzamidothiourea receptors switched on their ground-state charge transfer. An anion-binding induced structural change was suggested to occur around the N-N bond in N-benzamidothioureas, which resulted in a substantially increased electron donating ability of the electron donor in the receptor molecules. As a consequence, the ground-state charge transfer takes place in the N-benzamidothiourea-anion binding complexes, leading to unprecedented red shifts in the absorption spectra and substantially enhanced anion binding affinities than those of the corresponding N-phenylthiourea receptors. N-Benzamido-N'-phenylthioureas represent a new generation of neutral thiourea-based anion receptors that show substantially improved anion binding performance important for anion sensing and recognition.

Effects of the method of burning and addition of catalysts in the chimney of civil-used stove on emission of air pollutants were studied. Alumina-supported copper and manganese oxides and palladium catalysts were used to purify the flue gas emitted from the civil-used stoves. The results show that, in upper burning case, both Cu–Mn–O/Al 2 O 3 and Pd/CuO/Al 2 O 3 catalysts can decrease the ratio of CO/CO 2 to 2 and volatile organic chemicals (VOC) from the flue gas to some extent. Deactivation of the catalyst results from the accumulation of sulfate groups on catalyst support. The life of the catalyst can be extended by adding a honeycomb of lime before the catalyst.

Sulfate in groundwater has been previously shown to change the reactivity of Fe(0) in permeable reactive barriers for reducing chlorinated organics. To better understand the effect and mechanism of SO, the degradation of 1,1,1-trichloroethane (TCA) by Fe(0) in unbuffered aqueous solutions with and without SO was investigated. In a Fe(0) -TCA-H2 O system with initial pH of 2.0 to 10.0, the maximum removal rate of TCA was achieved at the initial pH 6.0 with pseudo-first-order constant Kobs 9.0 × 10(-3) /min. But in a Fe(0) -TCA-Na2 SO4 -H2 O system, the removal rate of TCA decreased remarkably with a reduction in Kobs to 1.0 × 10(-3) /min, and the pH varied from 6.0 to 9.6, indicating an inhibition of TCA dehydrochlorination by SO. Sulfate remarkably inhibited TCA degradation via changing the route of Fe(0) dissolution. It accelerated the dissolution of Fe(0) and transformed the intermediate form Fe(OH)ads to Fe2 (SO4 )ads , which weakened the affinity between Fe and TCA, and thus depressed the degradation of TCA by Fe(0) .

DER access to the distribution network will change the characteristics of power flow, the network short-circuit current levels and introduce a large number of harmonic interference in the traditional distribution network, which requires effective communication scheme as a monitor. In this paper, we analyze the requirements of the distribution of business and DER grid monitoring business, combined with the characteristics of a various types of communication, give a communication scheme of distribution network containing DERs. The program can be used as a reference for future distribution communication network construction with certain practical value.

Principles of design and production of dual-layer sub-wavelength grating microstructures are analyzed thoroughly. Novel methods for designing and fabricating such structures, with the characteristics of using rectangular grating index profiles when designed and using holographic interference lithography and coating processes when produced, are proposed. Microstructures fabricated by use of this method, will have the same resonant and optically variable properties with pre-designed structures, even improving its color qualities of lights reflected. A sub-wavelength security microstructure with the unique performances of red-green resonant complementary optically variability in color was designed and manufactured successfully and its resonant optically variable spectrum and color changing characteristics were verified theoretically and experimentally. Study results indicate that sinusoidal grating microstructures manufactured have the same resonant and optically variable characteristics, such as the resonant spectrum, color, spectral peak and peak splits, etc. with the pre-designed structures. A rectangular index profile grating is not the necessary requirement to produce resonance behaviors and the grating regions can have any profile such as the holographic type as long as its diffraction characteristics and equivalent waveguide representation are the same with the designed rectangular grating microstructures. The methods proposed are feasible in practice, lowering the making complexity and with potential of low-cost mass production commercially by use of the current holographic manufacture equipments.

This paper presents a complementary distributed generation (DG) with wind and photovoltaic powers. And it gives a detailed analysis of the effects for the various states of this DG to the island's voltage and frequency, and presents an optimization strategy called under-frequency load shedding in the island to increase the accuracy of model. On this basis, it builds a reliability analysis and calculation model for distribution network taking into the stochastic characteristics of the DG. Taking RBTS 6-bus distribution system for example, the reliability indices are calculated without DG, with the wind-power DG, with the photovoltaic DG and the complementary DG to system, to illustrate the rationality and validity of the model. And it verifies the DG making a role in improving the reliability of the distribution network, and compared to the same capacity DG with single energy power, the complementary DG is more competitive in improving the reliability of the distribution network system.

Heavy metals accumulated in slurry of dual alkali flue gas desulfurization (FGD) present a significant catalysis to SO3(2-) oxidation, resulting in a waste of effective components for desulfurization. Na2S was adopted to precipitate heavy metal ions in FGD slurry, and the oxidation rate of SO3(2-) was obtained under different concentrations of heavy metal ions, to reveal the inhibition effect of Na2S on SO3(2-) oxidation catalyzed by heavy metal ions. Mn2+ showed a remarkable catalysis to SO3(-2) oxidation, as the initial oxidation rate of SO3(2-) was tripled to 0.65 mmol/(L x min) by adding 1.0 mmol/L Mn2+ into the slurry. SO3(2-) was catalytically oxidized rapidly with the reaction order 0.169 of Mn2+ within first 60 minutes, so it is of great importance to control the concentration of Mn2+ to inhibit SO3(2-) oxidation. At initial pH value of 6.50-8.50, Na2S removed heavy metal ions effectively from FGD slurry. Higher pH value favored the removal of heavy metal ions. The removal efficiencies of Mn2+, Zn2+, Ni2+ and Cd2+ were 91.0%, 88.1%, 85.5%, and above 99.9% respectively under the conditions of initial pH value 8.50 and Na2S dosage 240.0 mg/L. Mn2+ could be used as an indicator for the concentration of the heavy metal ions in the slurry. As the Mn2+ concentration decreased from 1.0 mmol/L to 5.0 x 10(-3) mmol/L by adding Na2S, the initial oxidation rate of SO3(2-) decreased by 64.6% to 0.23 mmol/(L x min). The desulfurization efficiencies increase 3.8%-5.1% by adding Na2S in a pilot scale setup. It comes to conclusion that heavy metal ions precipitation by adding Na2S with an indicator of Mn2+ to inhibit catalytic oxidation of SO3(2-) is feasible to reduce the consumption of desulfurizer in FGD slurry.

The scientific, rational and practical electrical devices maintenance scheduling are helpful to improve the stability of power system operation and reduce the network damage caused by the equipment repair. This paper presents a new optimal algorithm to electrical devices maintenance scheduling optimal model. It sufficiently combines the advantages of the complex method and the genetic algorithm and remedies the drawbacks of each algorithm. In the hybrid intelligent algorithm, the complex method is embedded in genetic algorithm, being treated as one operator of the genetic algorithm. The new algorithm not only has the characters of the easy convergence and the powerful local optimization of the complex method, but also has the features of the powerful global search of the genetic algorithm. The practical examples verify the correctness and the validity of the hybrid intelligent algorithm and the superiorities comparing to the genetic algorithm.

N-(Acetamido)-N'-phenylthioureas (4-6) were found to be efficient anion receptors with higher anion affinity than their N-benzamido-N'-phenylthiourea counterparts (1 and 2). The N'-phenylthiourea moiety in 4-6 was shown to be the chromophore with an absorption maximum at ca. 270 nm. It was found that, in the presence of anions, the absorption at ca. 270 nm of 4-6 (except 5f) in acetonitrile (MeCN) was blue shifted and enhanced while a red-shifted shoulder appeared at ca. 295 nm, together with an isosbestic point at ca. 240 nm. The 1:1 anion binding constants of 4-6, for example at 10(6)-10(7) M(-1) order of magnitude for AcO(-) in MeCN, were found to be higher than those of 1 and 2, although the acidity of the thioureido -NH protons in 4-6 is lower than that in 1 and 2. (1)H NMR data indicates that the N-N single bond in 4-6 is twisted but less than that in 1 and 2. A conformation change at the N-N single bond of 4-6 was suggested to occur upon anion binding which leads to a planar hydrogen-bonding network in the anion binding complex in which a charge transfer takes place with the N-acyl moiety being the electron acceptor. Variations in the CD signals of a proline derivative 6 bearing a chiral center in the N-amido moiety provide direct evidence for this conformation change upon its binding with anions in MeCN. The amplified effect of substituent X at the N'-phenyl ring of 5 on the anion binding constant supports the conclusion of anion-binding switched charge transfer in the anion binding complex. (1)H NMR and absorption titrations for 5 indicated that the anion-receptor interaction was of a hydrogen-bonding nature until the N'-phenyl substituent X is as electron-withdrawing as m-CF(3) (5e). With X being the more electron-withdrawing p-NO(2) (5f), deprotonation of the thioureido -NH occurs in the presence of anion. Results reported here confirm that N-amidothioureas derived from both N-aliphatic and N-aromatic amides can in general be a family of efficient hydrogen-bonding receptors, with the aliphatic N-amido derivatives being more efficient. This provides a wider structural diversity for designing thiourea-based functional molecules such as anion receptors and organocatalysts. Preliminary experiments confirm that 6 could catalyse efficiently the reduction of nitrostyrene in CH(2)Cl(2) and MeCN.

Based on dynamic programming method, the unified planning mathematical model of multi-voltage substation is established. The model takes the voltage levels as phases, the location and sizing of new stations as decision-making, the power supply scope as state, and the annual cost of multi-voltage levels overall investment as objective function. In the paper, for locating and sizing of 110 substations, dynamic and weighted Voronoi (V) diagram planning method is presented, and an algorithm based on Cellular Automata for creating V diagram is designed; for locating and sizing of 220 substations, differential coefficient evolutional algorithm based on GIS is adopted. Due to considering the effect of unusable plots, ensures the practicability of new substation locations. Practical examples show that: the proposed method can satisfy the requirements of substation planning well, and obtained the good efficiency.

Studying the optimal subsection of distribution networks feeders, a subsection scheme synthesizing load and the length of subsections is presented. Hierarchical data envelopment analysis (DEA) method is proposed for multi-objective evaluation of subsection schemes. First, the scientific assessment system is established by using the analytic hierarchy process (AHP) and the weights of assessment criteria are derived from the judgment matrix. Secondly, the actual index data is used to structure DEA model, the schemes are evaluated quantificational with regard to different assessment criteria. Finally, each scheme is evaluated comprehensively. Using this method and the evaluation system to evaluate the subsection schemes, the evaluation results show that the assessment method is scientific and effective; the subsection method presented in this paper can better meet the economic and reliability requirements and is simple and practical.

The Substation Automation System (SAS) is a crucial element of power system control. The devices of SAS with remote-control functions are one of the main target of cyber attack. The vulnerability assessment for communication network of SASs that supporting the analysis of control process, is an unsolved problem. Combined with the characteristics of SAS and the vulnerability assessment of the distributed systems, a vulnerability assessment method for communication nework of SASs to cyber attack is proposed. The substation communication system has been classified into six basic models used to construct vulnerability state graph (VSG). The vulnerability of single action is defined based on exponential distribution function including parameters called vulnerability factor and equivalent attacking cost, and then the vulnerability value of target systems are calculated by four connection types of VSG. Furthermore, a vulnerability factor quantity method based on AHP-TOPSIS is designed. An evaluation instance is constructed from IEC 61850 standard, the proposed method is applicable to evaluate the vulnerability of communication network of SASs.

Studying the optimal subsection of distribution networks feeders, a subsection scheme synthesizing load and the length of subsections is presented. Hierarchical data envelopment analysis (DEA) method is proposed for multi-objective evaluation of subsection schemes. First, the scientific assessment system is established by using the analytic hierarchy process (AHP) and the weights of assessment criteria are derived from the judgment matrix. Secondly, the actual index data is used to structure DEA model, the schemes are evaluated quantificational with regard to different assessment criteria. Finally, each scheme is evaluated comprehensively. Using this method and the evaluation system to evaluate the subsection schemes, the evaluation results show that the assessment method is scientific and effective; the subsection method presented in this paper can better meet the economic and reliability requirements and is simple and practical.

In this paper, based on Centralized Distributed model, a study method of reliability of WAMS is presented. The whole WAMS system is divided into two sub-systems: Monitor Center System and Data Acquisition System. The Communication System is also modeled as an auxiliary evaluation system. According to the Markov condition, the Monitor Center System establishes the Kolomogorov equation, sets the invalidation function based on the GO software model, and obtains the evaluation methods of its availability. The analysis of Data Acquisition System takes the Phasor Measurement Unit and Phasor Data Concentrator (PDC), which installed in various protection areas, as the study objects, and gets the reliability evaluation of Data Acquisition System by the series system model, the parallel system model and k/n judgment system model of those facility units. The study method is used in the reliability evaluation of a real WAMS system of IEEE 14 Node. As the result shows that this reliability evolution method has a guiding significance in the practical application of WAMS system.

N-(Isonicotinamido)-N‘-(substituted-phenyl)thioureas (1a−e, substituent X = p-OCH3, p-CH3, H, m-Br, and m-CF3) have been designed as neutral receptors, in order to prove the influence of conformational issues on the ability to bind anions in aqueous solutions. Compounds 1a−e were shown to create a hydrophobic microenvironment around the thiourea group, favoring hydrogen bonding interactions, by evidence from quantum mechanic calculations, thermodynamic analysis, NMR aromatic current shielding, and comparative anion binding. Referring to N-(substituted-benzamido)thioureas (2a−e, substituent Y = H, m-Cl, m-NO2, m,m-Cl,Cl, and p-NO2), we showed that, for the hydrophobic microenvironment to be operative in aqueous solutions, the amido −NH proton needs to be acidic enough.