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Live working in distribution work is an important way to ensure normal power supply of power equipment. Live installation tool for robot operation was proposed in this paper in order to reduce the safety accidents occurrence. Through different structures and sensor combinations, it can complete the autonomous operation by cooperating with robot, including lead wire monitoring, line detection and tightening the puncture clamp. Finally, the finite element analysis of gear transmission was carried out, and the results showed that the design of the tool can mees the strength requirements.

ATP-sensitive potassium channels (KATP) are metabolic sensors that convert the intracellular ATP/ADP ratio to the excitability of cells. They are involved in many physiological processes and implicated in several human diseases. Here we present the cryo-EM structures of the pancreatic KATP channel in both the closed state and the pre-open state, resolved in the same sample. The nucleotides bind at the inhibitory sites of the Kir6.2 channel in the closed state but not in the pre-open state. Structural comparisons reveal the mechanism for ATP inhibition and Mg-ADP activation, two fundamental properties of KATP channels. Moreover, the structure also uncovers the activation mechanism of diazoxide-type KATP openers.

Three-dimensional scaffolds like hydrogels can be employed as cell carriers for in vitro or in vivo colonization and have become a major research topic to replace damaged tissue. In the current study, a novel composite hydrogel composed of sodium alginate (SA) and platelet-rich-plasma (PRP) varying in blending ratios, cross-linked with calcium ions, released from calcium carbonate-D-Glucono-d-lactone (CaCO3 -GDL) was successfully prepared. It was found that addition of PRP changed largely the physical properties and biological performance of the composite hydrogels, which was depending on the blending ratio. The gelation rate and swelling ratio of alginate hydrogels were significantly reduced by the addition of PRP, which produced also a more homogeneous gel structure. Field emission scanning electron microscopy (FE-SEM) investigation confirmed the incorporation of PRP-derived proteins in the hydrogel, where a porous structure with a pore size of 200-300 μm was found. On the other hand, an increase in surface roughness was observed after the addition of PRP. The compressive mechanical strength of SA/PRP composite hydrogel was enhanced in comparison to the pure SA gel. The composite hydrogels with the highest PRP content exhibited at a maximum compressive stress of 0.26 MPa a maximum strain of 55%, while the maximum compressive strain of pure SA hydrogels was only 45% at a stress of 0.08 MPa. It was also found that the in vitro degradation of the alginate gel was accelerated by the addition of PRP. In terms of cellular responses, all gels exhibited an excellent cytocompatibility. Indeed, the composite hydrogels supported bone marrow-derived mesenchymal stem cells proliferation and their chondrogenesis with up-regulation of chondrogenic marker genes Sox9 and Aggrecan. Overall, the present study suggests a great potential of SA/PRP composite hydrogels as cell carriers for cartilage tissue engineering.

Many organisms live in habitats with limited nutrients or space, competition for these resources is ubiquitous. Although spatial factors related to population’s manner of colonizing space influences its success in spatial competition, what these factors are and to what extent they influence the outcome remains under-explored. Here, we applied a simulated competitive model to explore the spatial factors affecting outcomes of competition for space. By quantifying spatial factors using ‘Space Accessibility’, we show that colonizing space in an anti-aggregation manner contributes to microbial competitive success. We also find that the competitive edge derived from being anti-aggregation in colonizing space, which results in a higher ‘Space Accessibility’, neutralizes the disadvantage arising from either lower growth rate or lower initial abundance. These findings shed light on the role of space colonization manners on maintaining biodiversity within ecosystems and provide novel insights critical for understanding how competition for space drives evolutionary innovation.

BACKGROUND: Ambient air pollution has been characterized as a leading cause of mortality worldwide and has been associated with cardiovascular and respiratory diseases. There is increasing evidence that short-term exposure to nitrogen dioxide (NO(2)), is related to adverse health effects and mortality. METHODS: We conducted a systematic review of short-term NO(2) and daily mortality, which were indexed in PubMed and Embase up to June 2021. We calculated random-effects estimates by different continents and globally, and tested for heterogeneity and publication bias. RESULTS: We included 87 articles in our quantitative analysis. NO(2) and all-cause as well as cause-specific mortality were positively associated in the main analysis. For all-cause mortality, a 10 ppb increase in NO(2) was associated with a 1.58% (95%CI 1.28% to 1.88%, I(2) = 96.3%, Eggers’ test p < 0.01, N= 57) increase in the risk of death. For cause-specific mortality, a 10 ppb increase in NO(2) was associated with a 1.72% (95%CI 1.41% to 2.04%, I(2) = 87.4%, Eggers’ test p < 0.01, N= 42) increase in cardiovascular mortality and a 2.05% (95%CI 1.52% to 2.59%, I(2) = 78.5%, Eggers’ test p < 0.01, N= 38) increase in respiratory mortality. In the sensitivity analysis, the meta-estimates for all-cause mortality, cardiovascular and respiratory mortality were nearly identical. The heterogeneity would decline to varying degrees through regional and study-type stratification. CONCLUSIONS: This study provides evidence of an association between short-term exposure to NO(2), a proxy for traffic-sourced air pollutants, and all-cause, cardiovascular and respiratory mortality.

Conjugate heat transfer (CHT) has been widely used in the analysis on flow field and heat transfer of turbine blades. In this paper, a baseline design of turbine rotor blade is selected. By improving the arrangement of film holes, turning cylindrical holes into laid back fan-shaped holes in the pressure surface (PS) and suction surface (SS), and reducing the radially inclined angle of film holes on the leading edge (LE), an optimized design (OPT) is created. Grid independence validation is conducted by comparing the pressure and temperature distributions adopting three different numbers of grids. In order to select a suitable turbulence model, experiment is performed and its values are compared with the calculation results of three different turbulence models. The distributions of static pressure, static temperature, overall cooling effectiveness and streamlines of cooling flow are compared between the OPT and baseline design by the numerical calculation results of CHT. Furthermore, the adiabatic film cooling effectiveness is calculated and the cooling performances between cylindrical holes and laid-back fan-shaped holes are compared. At last, the flow and heat transfer mechanisms are analyzed and the forming causes of low or high temperature regions on the blade are explained. Calculation results show that compared with the baseline design, the area average temperature drops by 2.6% on the PS and by 3.7% on the SS. The area average overall cooling effectiveness increases by 9.3% on the PS and by 14.1% on the SS. The cooling performances are promoted greatly on the PS and SS but change little on the LE and TE. Obviously, the improvements are successful.

To improve the cooling performance of the turbine guided vane, conjugate heat transfer is utilized to investigate the internal and external cooling systems in real working conditions. The purpose is to increase the overall cooling effectiveness with limited influence on coolant consumption and cascade pressure loss factors. Firstly, the internal cooling is improved to enhance heat transfer by installing impingement cooling, ribs, dimples, and protrusions. Then, by adopting film holes near the shroud and hub, the coolant coverage of the external cooling is improved. To explain the influence of structure modification, the flow field is analyzed while the blockage effect of various structures on the crossflow is compared. The flow mechanism of conical dimples and protrusions is concluded. Results show that the improvement in internal cooling enhances heat transfer and decreases coolant consumption. However, the external film cooling deteriorates. By installing dimples and protrusions, the effusion condition of jet nozzles deteriorates. Dimples have higher heat transfer performance than protrusions. By improving external cooling, increases in film cooling effectiveness, discharge coefficients of jet nozzles, and heat transfer can be found. However, the coolant consumption increases. At Reynolds number of 15003–19599, the best-performing structure, by combining impingement/effusion cooling with ribs and protrusions, increases overall cooling effectiveness by 0.54–8.01% and 9.81–11.62% on the pressure surface and suction surface respectively. However, changes in coolant consumption (0.63–2.45%) and cascade pressure loss factors (−7.51–4.81%) are limited. The improvement thoughts and influence factors on the cooling performance are concluded, serving as guidance for the vane design.

Effective and accurate diagnostic methods are necessary to ensure the stable and efficient operation of proton exchange membrane fuel cells (PEMFC). In practice, the voltage drop is commonly used as the detection indicator of the flooding fault. However, the output power changes also affect the voltage of the PEMFC. To better diagnose the flooding fault under load-varying conditions, a data-driven method for PEMFC using deep learning technologies is proposed, which can automatically extract fault features for the raw data to diagnose the flooding fault. First, the indicators for the fault diagnosis model are selected to meet the actual situation according to the water transport mechanism and auxiliary systems of the general fuel cell stack. And the collected data are transformed into a 2-D graph to visually represent the characteristics of the time-series data. Then, the convolutional neural network is adopted to develop the fault diagnosis model. In addition, the batch normalization method is used to alleviate feature distribution differences and enhance the model generalization. Finally, the trained model is applied to detect the flooding fault. A real PEMFC experiment dataset is adopted to verify the diagnostic performance of the method. Experiment results show that the proposed model can effectively identify the flooding fault of the fuel cell accurately under load-varying conditions, and achieves over 99% accuracy.

With the develofpment of UWB electromagnetic pulse radiation systems, people are paying more and more attention to its serious threat to electronic equipment. The effect of UWB electromagnetic pulse has also become an important content in the field of electromagnetic compatibility. In an UWB radiation system, the distance between the device under test and the transmitting antenna is different, and the radiation field received is also different. Therefore, in actual tests, the test body is often placed at different distances from the antenna to perform multiple measurements to obtain test data as required. Based on this, this article takes the cavity as an example, and proposes a method of using the system transfer function to predict the response of the impulse field inside the cavity to simplify the test and quickly obtain the test data. Firstly, the impulse field response of a certain point with and without a cavity is measured respectively, and then the time domain response is inversely Fourier transformed to obtain the frequency domain transfer function of the test body. Finally, using the transfer function to convolute with the field to be measured, the response of the impulse field inside the cavity can be predicted under the condition of the field to be measured. It is verified by experiments that this method can better predict the response of the impulse field inside the cavity under different distance conditions, and has the characteristics of simple calculation and good prediction effect. At the same time, the transfer function obtained by this method can be used to predict the arbitrary impulse field response of the cavity in its frequency range.

How to use the amplitude-frequency characteristics to reconstruct the signal to obtain the time-domain response has always been a concern in the field of nuclear electromagnetic protection. So far, in practical applications, parametric modeling and non-parametric modeling have been used to solve related problems. This article summarizes the research and development of using amplitude-frequency characteristics to recover time-domain signals in the field of nuclear electromagnetic pulse protection, and briefly introduces the shortcomings of the two methods in combination with specific experiments.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), characterized by a large number of inflammatory cell aggregation and alveolar cell damage in pathophysiology, have extremely high morbidity and mortality in critically ill patients. In recent years, more and more studies have found that there are abundant extracellular vesicles (EVs) in animal models and patients with ALI/ARDS, and they play a critical role in the pathogenesis of lung injury. Clarifying the mechanisms of EVs in lung injury is of great significance in the diagnosis and treatment of ALI/ARDS. In this review, we will summarize the recent findings on the roles of EVs derived from different cells in ALI/ARDS, along with the formation, function, and related effects of EVs, and explore their potential clinical application for the diagnosis and treatment of ALI/ARDS.

To explore the editing specificity of CRISPR/Cpf1 system, effects of target mutation were systematically examined using a reporter activation assay, with a set of single-nucleotide mutated target site. Consistent with our previous study performed with CRISPR/Cas9, a “core” sequence region that is highly sensitive to target mutation was characterized. The region is of 4-nucleotide long, located from +4 to +7 position of the target site, and positioned within a positively charged central channel when assembled into Cpf1 endonuclease. Single-nucleotide mutation at the core sequence could abolish gene editing mediated by a however active sgRNA. With a great majority of the target sites, a kind of ‘super’ off-target gene editing was observed with both CRISPR/Cpf1 and CRISPR/Cas9. For a given target site, mutation at certain positions led to greatly enhanced off-target gene editing efficacy, even up to 10-fold of that of the fully-matched target. Study further found that these effects were determined by the identity of target nucleotide, rather than the nucleotide of crRNA. This likely suggests that the interactions between target nucleotide and the endonuclease are involved in this process.

Data are reported for intelligence of children in China assessed by the Combined Raven's Test in 1988, 1996 and 2006. The IQ of the samples increased by 15.0 IQ points over 18-year period. The British IQ of China in 1988 and 2006 is estimated as 94.8 and 109.8, respectively.

In engines, torsional vibration is inevitably caused by the fluctuation of the engine torque. Therefore, the establishment of torsional vibration damper is the necessary measure to diminish the torsional vibration. In this paper, an experimental study was carried out in a gasoline engine to analyze the bolt tightening of torsional vibration damper. The influence of the friction coefficient of the bolt of the torsional vibration damper, the material properties of the torsional vibration damper, and the axial force calibration were studied. The results show that the changes in the friction coefficient of the bolt and the material of the torsional vibration damper have great impacts on the bolt torque. It is effective to improve the bolt tightening state by checking the axial force and establishing suitable tightening parameters.

Bladder cancer is one of the most commonly diagnosed malignant tumors in the urinary system and causes a massive cancer-related death. DEPDC1B is a DEP domain-containing protein that has been found to be associated with a variety of human cancers. This study aimed to explore the role and mechanism of DEPDC1B in the development of bladder cancer. The analysis of clinical specimens revealed the upregulated expression of DEPDC1B in bladder cancer, which was positively related to tumor grade. In vitro and in vivo studies showed that DEPDC1B knockdown could inhibit the growth of bladder cancer cells or xenografts in mice. The suppression of bladder cancer by DEPDC1B was executed through inhibiting cell proliferation, cell migration, and promoting cell apoptosis. Moreover, a mechanistic study found that SHC1 may be an important route through which DEPDC1B regulates the development of bladder cancer. Knockdown of SHC1 in DEPDC1B-overexpressed cancer cells could abolish the promotion effects induced by DEPDC1B. In conclusion, DEPDC1B was identified as a key regulator in the development of bladder cancer, which may be used as a potential therapeutic target in the treatment of bladder cancer.

Proteins were first used in the early 1960s to discover the molecular clock dating method and remain in common usage today in phylogenetic inferences based on neutral variations. To avoid substitution saturation, it is necessary to use slow evolving genes. However, it remains unclear whether fixed and standing missense changes in such genes may qualify as neutral. Here, based on the evolutionary rates as inferred from identity scores between orthologs in human and Macaca monkey, we found that the fraction of conservative amino acid mismatches between species was significantly higher in slow evolving proteins. We also examined the single nucleotide polymorphisms (SNPs) by using the 1000 genomes project data and found that missense SNPs in slow evolving proteins also had higher fraction of conservative changes, especially for common SNPs, consistent with more natural selection for SNPs, particularly rare ones, in fast evolving proteins. These results suggest that fixed and standing missense variations in slow evolving proteins are more likely to be neutral and hence better qualified for use in phylogenetic inferences.

In order to effectively improve the effect of state unobservable intelligent substation secondary equipment state evaluation and reduce the influence of uncertain factors on the evaluation result, a fuzzy set theory-based intelligent substation secondary equipment state evaluation method is proposed and applied. Firstly, we conduct hierarchical modeling for the intelligent substation and enumerate the different factors affecting the equipment state. Then, the probability of different events affecting the state of the secondary equipment is determined by using the fuzzy set theory and expert knowledge, and the probability of each event is quantified to obtain the secondary equipment state occurrence interval probability. After defuzzification, the state evaluation results of secondary equipment are obtained. Therefore, a conclusion is drawn that this evaluation method of secondary equipment state assessment in intelligent substation based on fuzzy set theory can make more accurate state evaluation, greatly reduce the influence of subjective factors on the evaluation results, and make the evaluation results more stable, reliable and scientific.

Background Ambient air pollution is among the greatest environmental risks to human health. However, little is known about the health effects of nitrogen dioxide (NO2), a traffic-related air pollutant. Herein, we aimed to conduct a meta-analysis to investigate the long-term effects of NO2 on mortality. Methods We conducted a systematic search for studies that were published up to February 2020 and performed a meta-analysis of all available epidemiologic studies evaluating the associations between long-term exposure to NO2 with all-cause, cardiovascular, and respiratory mortality. Overall pooled effect estimates as well as subgroup-specific pooled estimates (e.g. location, exposure assessment method, exposure metric, study population, age at recruitment, and key confounder adjustment) and 95% confidence intervals were calculated using random-effects models. Risk of bias assessment was accessed by following WHO global air quality guidelines. Publication bias was accessed by visually inspecting funnel plot and Egger's liner regression was used to test of asymmetry. Results Our search initially retrieved 1349 unique studies, of which 34 studies met the inclusion criteria. The pooled hazard ratio (HR) for all-cause mortality was 1.06 (95%CI: 1.04–1.08, n = 28 studies, I2 = 98.6%) per 10 ppb increase in annual NO2 concentrations. The pooled HRs for cardiovascular and respiratory mortality per 10 ppb increment were 1.11 (95%CI: 1.07–1.16, n = 20 studies, I2 = 99.2%) and 1.05 (95%CI: 1.02–1.08, n = 17 studies, I2 = 94.6%), respectively. The sensitivity analysis pooling estimates from multi-pollutant models suggest an independent effect of NO2 on mortality. Funnel plots indicate that there is no evidence for publication bias in our study. Conclusion We provide robust epidemiological evidence that long-term exposure to NO2, a proxy for traffic-sourced air pollutants, is associated with a higher risk of all-cause, cardiovascular, and respiratory mortality that might be independent of other common air pollutants.

The development of micromanipulation technology has an important impact on the research in the microfield, which mainly focuses on the preparation and assembly of microcomponents, in which the microcomponent picking technology is used. The existing picking methods mainly use manipulation tools to clamp or adsorb components, which may destroy or fail to pick objects in the process of manipulation, and the efficiency is relatively low. In order to solve the problems in the existing manipulation methods, a new metal microcomponent picking method based on electrochemistry is proposed, which mainly uses the electrochemical principle to produce metal deposition, connect the manipulation tool and the object, and indirectly control the object by moving the manipulation tool. In this paper, the simulation software ABAQUS is used to pick up the microcopper wires with the length of 100, 200 and 300 [Formula: see text]m by using a pipette with a nozzle diameter of 15 [Formula: see text]m. The force curve between the tool and the object during the manipulation process is obtained. The feasibility of the method is verified by theoretical analysis and simulation experiments.

Narrative reports suggest that socioeconomic status (SES) is associated with biogeographic ancestry (BGA) in the Americas. If so, SES potentially acts as a confound that needs to be taken into account when evaluating the relation between medical outcomes and BGA. To explore how systematic BGA-SES associations are, a meta-analysis of American studies was conducted. 40 studies were identified, yielding a total of 64 independent samples with directions of associations, including 48 independent samples with effect sizes. An analysis of association directions found a high degree of consistency. The square rootn-weighted directions were 0.83 (K=36), -0.81 (K= 41) and -0.82 (K= 39) for European, Amerindian and African BGA, respectively. An analysis of effect size magnitudes found that European BGA was positively associated with SES, with a meta-analytic effect size ofr= .18 [95% CI: .13 to .24,K= 28,n= 35,476.5], while both Amerindian and African BGA were negatively associated with SES, having meta-analytic effect sizes of -.14 [-.18 to -.10,K= 31,n= 28,937.5] and -.11 [-.15 to -.07,K= 28,n= 32,710.5], respectively. There was considerable cross-sample variation in effect sizes (mean I2= 92%), but the sample size was not enough for performing credible moderator analysis. Implications for future studies are discussed.

This study reports the associations between the intelligence of children aged 8–10 years across thirty-one provinces and municipalities of the People's Republic of China and their economic and social correlates. It was found that regional IQs were significantly correlated at the p r = 0.75), GDP per capita ( r = 0.73), and years of education ( r = 0.76). Results of a multiple regression analysis showed that regional IQs were the only significant predictor of regional differences in the GDP per capita accounting for 56% of the variance.

The relationship between fertility, intelligence, and education was examined in China using a large sample sourced from the population-representative China Family Panel Studies (CFPS) dataset. For the 1951–1970 birth cohort, the correlation between fertility and gf was −.10. The strength of recent selection against gf in China substantially increased between the 1960s and the mid-1980s. Later (between 1986 and 2000), the speed of decline in gf due to selection stabilized at about .31 points per decade with a slightly downward trend. The total loss from 1971 to 2000 due to dysgenic fertility is estimated to be .75 points. A negative relationship between educational attainment and fertility was additionally found. Both negative relations were stronger for women.

According to the statistics of Wuhan, the prediction model of vehicle population based on econometrics is established, the vehicle population of last year is especially considered in this model as a variable of representation of consumer psychology, therewith regression coefficients and related statistic parameters are calculated through MATLAB in this paper, and solid tests on the model are conducted as well. After model adjusted, the vehicle population of Wuhan in 2016 is eventually calculated. The result is comparatively accurate, indicating it is a technically feasible method. The vehicle population of Wuhan in 2017 is predicted in this paper as well.

Among the phosphofructokinase B-type carbohydrate kinase (PCK) family proteins, only few proteins, like the FRUCTOKINASE-LIKE 1 and 2, have been functionally characterized in regulation of chloroplast development. Here, we report the involvement of a PCK protein PFKB1 in chloroplast development by identification of a new rice mutant, revertible early yellowing Kitaake 2 [rey(k2)]. The mutant rey(k2) shows yellow leaf phenotype, reduced photosynthetic pigments, and retarded chloroplast development during early stages of seedlings, but gradually recovered at later stages. The phenotype of rey(k2) is resulted from the disruption of the PFKB1 protein. The Pfkb1 gene is ubiquitously expressed, and its protein is mainly targeted to the chloroplast and, in some cells, to the nucleus. In addition, the PFKB1 protein possesses phosphofructokinase activity in vitro. The rey(k2) mutant affects RNA levels of chloroplast-associated genes. In particular, the nuclear-encoded RNA polymerase (NEP)-dependent genes are expressed at a sustained high level in rey(k2) even after turning green, indicating that PFKB1 is essential for suppressing the expression of NEP-dependent genes. Taken together, our study suggests that PFKB1 functions as a novel regulator indispensable for early chloroplast development, at least partly by regulating chloroplast-associated genes.

Tunable ZnS–CuS microspheres were readily prepared via replacing the Zn2+ ions of solid ZnS microspheres with Cu2+ ions in an aqueous solution under a hydrothermal condition, and were then characterized by XRD, SEM, TEM, UV-Vis, PL and XPS techniques. The thickness of CuS shell on the surface of ZnS core can be controlled by changing the ion-exchange time, which plays an important role in the visible light photodegradation efficiency of rhodamine B in aqueous solution. Degradation rate can rapidly reach ca. 72% under visible light irradiation for 15 min and then ca. 98% after 60 min using the ZnS–CuS microspheres as the photocatalyst.

The neutral theory has been used as a null model for interpreting nature and produced the Recent Out of Africa model of anatomically modern humans. Recent studies, however, have established that genetic diversities are mostly at maximum saturation levels maintained by selection, therefore challenging the explanatory power of the neutral theory and rendering the present molecular model of human origins untenable. Using improved methods and public data, we have revisited human evolution and found sharing of genetic variations among racial groups to be largely a result of parallel mutations rather than recent common ancestry and admixture as commonly assumed. We derived an age of 1.86-1.92 million years for the first split in modern human populations based on autosomal diversity data. We found evidence of modern Y and mtDNA originating in East Asia and dispersing via hybridization with archaic humans. Analyses of autosomes, Y and mtDNA all suggest that Denisovan and Neanderthal were archaic Africans with Eurasian admixtures and ancestors of South Asia Negritos and Aboriginal Australians. Verifying our model, we found more ancestry of Southern Chinese from Hunan in Africans relative to other East Asian groups examined. These results suggest multiregional evolution of autosomes and replacements of archaic Y and mtDNA by modern ones originating in East Asia, thereby leading to a coherent account of modern human origins.

L'Association pour la promotion de la traduction littéraire (ATLAS) et la BULAC présentent, dans le cadre de la Fabrique des traducteurs, une soirée "Encres fraîches de l’atelier français-chinois" : lectures, mises en voix par Dominique Léandri, par les traducteurs Eva Fischer, Cao Dongxue, Lucie Modde, Tou Chiu Zong, Claire Raybaud, Wang Mingrui, suivies d'une rencontre. Lectures par les traducteurs d'extraits de :- Récit de Bi Feiyu, traduit par Eva Fischer- Chéri de Colette, traduit par Cao Dongxue- Attends et autres nouvelles de Lao Ma, traduit par Lucie Modde- Les Contes d’Amadou-Koumba de Birago Diop, traduit par Tou Chiu Zong- J’aime ma maman de Chen Xiwo, traduit par Claire Raybaud- L’Astragale d’Albertine Sarrazin, traduit par Wang Mingrui.

Substation inspection has already benefited from developments in mobile robotics. Since 2002, over 10 substation inspection robots have been developed at Shandong Electric Power Institute. These robots carry visible light cameras and infrared thermographs which are used to detect invaders and equipments fault respectively. They move inside the substation and position for collecting images of possible critical points. This paper presents a review of some key techniques of these robots, such as autonomous navigation, autonomous battery charging and autonomous equipment recognition.

Various kinds of copper sulfides (CuS, a mixture of Cu7S4–CuS and Cu9S5) were synthesized by simply adjusting the amount of copper chloride and sodium sulfide in a solvothermal process. The different molar ratios of copper chloride and sodium sulfide result in the formation of different kinds of copper sulfides with various morphologies, such as tiny particle, hexagonal plate and octahedron. The products were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. And the optical properties of the products were recorded by means of UV-Vis absorption and photoluminescence spectroscopy. Moreover, due to the presence of visible light, we found that the catalytic activities of the products for oxidation and decomposition of Rhodamine B with the assistance of hydrogen peroxide were enhanced, and the degradation efficiency of RhB was increased from 40% to 98% in 15 minutes at room temperature.

Fluorescent semiconductor nanocrystals have been widely used as fluorescent materials in chemical sensors, biotechnology, medical diagnostics, biological imaging and many other fields. Compared to the conventional organic fluorophores, the inorganic quantum dots (QDs) have many advantages, including broad absorption spectra, narrow emission spectra, good photostability and long fluorescent lifetime after excitation. Here, the high quality CdS QDs were synthesized directly from sulfur and CdO using the paraffin liquid as solvent and the oleic acid as the reacting media. The synthesized CdS QDs with a zinc blende (cubic) crystal structure were proved by X-ray diffraction. HRTEM observation revealed that the CdS QDs were uniform and the average grain size was about 4 nm. The optical properties of the CdS QDs were characterized by using photoluminescence (PL) spectrophotometer and Ultraviolet-visible (UV-Vis) absorption spectrophotometer. The formation mechanism of CdS QDs in the paraffin liquid and oleic acid system was proposed.