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Due to the influence of extreme rainfall and high intensity human engineering activities, the advance speed of the gully head in the Loess Tableland is intensified, which seriously threatens the economic and social development of the Loess Tableland. In recent years, although large-scale Gully Consolidation and Highland Protection (GCHP) projects have effectively inhibited the development of traceable erosion on Loess tableland, there are still serious problems of soil and water erosion. Based on this situation, this study investigated and analyzed the soil erosion diseases of the typical GCHP Projects through field investigation, literature review, and comprehensive analysis. The results show that the hydrology regulation function of GCHP Projects can be divided into the table-land intercept area, gully head cut row area, gully slope cutting line of energy dissipation, and channel held area. Currently, the GCHP suffers from surface water erosion, subsurface erosion of loess engineering geological interface, blockage of drainage channels, and disaster chain of loess gully. The unclear hydrological control mechanism and the mechanism of soil and water mutual feeding erosion disasters are the key scientific challenges of the project. In the future, attention should be paid to the application of biological soil crust, new soil improvement materials, and the complete quality supervision of gully protection tableland engineering. This study can provide basic information for future research on the mechanism of soil and water erosion disasters and engineering planning and design of the Gugou Plateau.

Diabetic foot ulcers, pressure ulcers, and bedsores can easily develop into chronic wounds with bacterial infections, complicating wound healing. This work reports a two-step strategy for treating infected chronic wounds. Firstly, LL37 mimetic peptide-W379 peptides were rapidly released to eliminate the bacterial biofilm on the wound. Then, 3D radially aligned nanofiber scaffolds loaded with W379 antimicrobial peptide and PDGF-BB were used to treat the wound to prevent bacterial infection recurrence and promote angiogenesis and granulation tissue regeneration, thereby accelerating wound healing. In the presented study, we found that the combined use of burst and controlled release of W379 antimicrobial peptide effectively clears the bacterial biofilm and prevents the recurrence of bacterial infection. Additionally, we found that the removal of the bacterial biofilm contributed to modulating the local inflammatory response from a pro-inflammatory type to a pro-regenerative type. Furthermore, the use of PDGF-BB significantly promotes neovascularization and granulation tissue regeneration in the wound bed, resulting in accelerating re-epithelialization and wound closure. Our study provides a promising treatment method for the repair of infected chronic wounds.

IntroductionInternal erosion triggered by water pipeline leaks seriously threatens the stability of the urban ground. Hangzhou, a city in Zhejiang Province, China, is facing critical challenges due to urban ground collapse (UGC) caused by internal erosion. However, there is a lack of research on the prevention of UGC by improving the internal erodibility of underground soil. Addressing this issue is of utmost importance to ensure the city’s stability and safety. This paper proposes to improve the internal erodibility of typical sandy silt soils with chemical stabilisers.MethodsThe effects of three chemical stabilisers, lignosulphonate (LS), lime (LI), and lignin fibre (LF), on the critical shear stress (τc) and erosion coefficient (kd) of sandy silt soils were investigated, which from Hangzhou, Zhejiang, China, by the hole erosion test (HET) at different mixing amounts and at different conservation times.ResultsThe findings indicate that LF mainly improves the erosion resistance of sandy silt by increasing τc, and the maximum increase is 2.38 times; LI mainly improves the erosion resistance by decreasing kd, and the maximum decrease is 2.18 times. After adding LS, τc and kd did not change significantly. The scanning electron microscope (SEM) test revealed that the inclusion of LF led to the formation of larger agglomerates in the sandy silt soil. The microstructure of sandy silt soil remained dispersed even after adding LS. Various chemical stabilisers used to improve sandy silt soils exhibited distinct erosion mechanisms. Sandy silt soils improved with LF exfoliated into agglomerates, displaying high resistance to erosion. On the other hand, the sandy silt treated with LF still lacks a protective layer and shows minimal improvements in its ability to withstand erosion. In contrast, the LS-amended sandy silt remains stripped with individual soil particles with insignificant changes in erosion resistance.DiscussionThis study can provide a conceptual framework for choosing foundation treatment techniques in future urban development projects.

Background Individuals suffering from chronic kidney disease (CKD) frequently face a heightened likelihood of experiencing cardiovascular complications, including heart failure and cardiac mortality. Cardiovascular magnetic resonance feature tracking (CMR-FT) is utilized to assess the micro-contraction function of the myocardium. The objective of this research is to explore the relationship between the left ventricular anatomy, myocardial strain, and the clinical outcomes in patients with CKD. Methods A total of 77 patients with late-stage CKD were enrolled in this retrospective study. They underwent cardiac magnetic resonance imaging and were followed up, with no history of significant cardiac diseases. The patients were divided into two groups: those with a left ventricular global longitudinal strain (LVGLS) ≥ −15.2% (n = 49) and those with LVGLS < −15.2% (n = 28). The clinical endpoints were defined as hospitalization for heart failure or all-cause mortality. Results Over an average observation period of 22 ± 9 months, 11 (14%) patients passed away and 30 (39%) were admitted to the hospital for heart failure, with eight encountering both incidents. Those with LVGLS ≥ −15.2% had markedly lower rates of event-free survival concerning heart failure admissions and overall mortality than their counterparts (log-rank P = 0.014). Cox multivariable analysis indicated that reduced LVGLS consistently predicted a higher likelihood of combined outcomes of heart failure admissions and total mortality (HR: 3.40, 95% CI [1.35–8.56], P = 0.009), even when factoring in age, diabetes, left atrial diameter, and left ventricular mass index (LVMI). However, the LVMI showed no significant correlation with the risk of heart failure admissions or overall mortality. Conclusion Compared to patients with LVGLS < −15.2%, CKD patients with LVGLS ≥ −15.2% have an increased risk of heart failure hospitalization and all-cause mortality. The prognostic role of LVMI in assessing CKD patients among the Asian population requires further investigation.

The formation mechanism of caves in fissured loess at the edge of the loess platform plateau is complex and is closely related to the occurrence of geological hazards such as landslides, which pose a serious threat to the production and life of people in this region. To address the scientific problem of how internal erosion caves are formed in the fissured loess, four sets of experiments on the formation mechanism of internal erosion caves in loess under different initial fissure opening conditions are carried out using the visualisation of the internal erosion caves formation mechanism model of the fissured loess in the South Plateau of Jingyang as a reference. The results show that the development process from the fractured loess to the internal erosion of caves under water flowing erosion can be divided into three stages, including the hydraulic erosion stage, the infiltration and erosion stage and the gravity collapse stage. The formation mechanism of the internal erosion caves in the fractured loess can be summarized as follows: Softening and sputtering, scouring and widening, erosion and cavitation, and collapsing by gravity. The development rate of seepage erosion in the fractured loess is reflected by the sediment quantity and transport characteristics, which can be divided into the rapid erosion stage, the fluctuation reduction stage and the slow and stable erosion stage. The fracture opening, the erodibility of loess and the ultimate groove depth are important factors affecting the formation of internal erosion caves in the fractured loess. The research results provide theoretical support to further reveal the disaster-causing effects of loess internal erosion.

BackgroundStreptococcus pneumoniae is a common pathogen that colonizes the human upper respiratory tract, causing high morbidity and mortality worldwide. This study aimed to investigate the prevalence status of S. pneumoniae isolated from patients of all ages in Southwest China, including serotype, antibiotic susceptibility and other molecular characteristics, to provide a basis for clinical antibiotic usage and vaccine development.MethodsThis study was conducted from January 2018 to March 2022 at West China Hospital, West China Second University Hospital, First People’s Hospital of Longquanyi District (West China Longquan Hospital), Meishan Women and Children’s Hospital (Alliance Hospital of West China Second University Hospital) and Chengdu Jinjiang Hospital for Women and Children Health. Demographic and clinical characteristics of 263 pneumococcal disease (PD) all-age patients were collected and analyzed. The serotypes, sequence types (STs), and antibiotic resistance of the strains were determined by next-generation sequencing, sequence analysis and the microdilution broth method.ResultsThe most common pneumococcal serotypes were 19F (17.87%), 19A (11.41%), 3 (8.75%), 23F (6.46%) and 6A (5.70%). Coverage rates for PCV10, PCV13, PCV15, PCV20 and PCV24 were 36.12, 61.98, 61.98, 63.12 and 64.26%, respectively. Prevalent STs were ST271 (12.55%), ST320 (11.79%), ST90 (4.18%), ST876 (4.18%) and ST11972 (3.42%). Penicillin-resistant S. pneumoniae (PRSP) accounted for 82.35 and 1.22% of meningitis and nonmeningitis PD cases, respectively. Resistance genes msrD (32.7%), mefA (32.7%), ermB (95.8%), tetM (97.3%) and catTC (7.6%) were found among 263 isolates. Most isolates showed high resistance to erythromycin (96.96%) and tetracycline (79.85%), with more than half being resistant to SXT (58.94%). A few isolates were resistant to AMX (9.89%), CTX (11.03%), MEN (9.13%), OFX (1.14%), LVX (1.14%) and MXF (0.38%). All isolates were susceptible to vancomycin and linezolid.ConclusionOur study provides reliable information, including the prevalence, molecular characterization and antimicrobial resistance of S. pneumoniae isolates causing pneumococcal diseases in Southwest China. The findings contribute to informed and clinical policy decisions for prevention and treatment.

To ensure the safety of life and property of residents on landslides and reveal the deformation and failure law of masonry buildings on landslides, it is necessary to carry out a simulation study on the deformation and failure process of masonry buildings under the action of landslide deformation. A refined model of a masonry building was established based on the contact separation modeling method in ABAQUS, and the viscous contact interface was used to simulate the effect of mortar in the wall. Comparing the results of the numerical simulation with the physical model test results, the main conclusion is as follows: through the comparison of macroscopic deformation characteristics and microscopic stress and strain data obtained from physical and numerical model tests, the load-strain curve of the numerical model test agrees well with that of the physical model test, and their strain clouds are consistent, proving the validity of the numerical simulation method. The law of crack propagation and strain distribution of building walls in landslide tension areas is revealed, which can provide a basis for the protection design of masonry buildings in landslide tension areas.

Pr-doped metal oxide polycrystalline transparent ceramics are highly desirable for photothermal window systems served in extreme environments; however, obtaining efficient photoluminescence (PL) together with high transparency in these ceramics is still posing serious challenges, which undoubtedly limits their applications. Here, Pr-doped Y2Zr2O7 (YZO) transparent ceramics, as an illustrative example, are prepared by a solid-state reaction and vacuum sintering method. Owing to the elimination of defect clusters [PrY4+−O2−−PrY4+] and [PrY4+−e′] without the introduction of impurities and additional defects, the fabricated YZO:Pr ceramics exhibit high transparency (74%) and efficient PL (39-fold enhanced) after air annealing plus vacuum re-annealing treatment. Moreover, upon 295/450 nm excitation, the emission bands (blue, green, red, and dark red) from YZO:Pr ceramics present different temperature-dependent properties due to the thermal-quenching channel generated by the intervalence charge transfer (IVCT) state between Pr3+ and Zr4+ ions. Furthermore, a self-calibrated temperature feedback window with the same fluorescence intensity ratio (FIR) model (I613/I503, where I represents the intensity) under different excitation light sources (295 and 450 nm) is designed. The developed photothermal window operated in a wide temperature range (303–663 K) shows relatively high sensitivities (absolute sensitivity (Sa) and relative sensitivity (Sr) reach 0.008 K−1 at 663 K and 0.47% K−1 at 363 K, respectively), high repeatability (> 98%), and low temperature uncertainty (δT < 3.2 K). This work presents a paradigm for achieving enhanced PL along with elevated transparency of lanthanide (Ln)-doped ceramics through vacuum re-annealing treatment engineering and demonstrates their promising potential for photothermal window systems.

Abstract Background The purpose of this study was to demonstrate both the four-year prevalence trend of healthcare-associated infections (HAIs) in a large tertiary hospital and the trend regarding the prevalence of HAIs following the outbreak of coronavirus disease 2019 (COVID-19) in order to provide evidence of hospital infection management during the COVID-19 pandemic. Methods Based on the hospital’s electronic nosocomial infection databases related to HAIs, we retrospectively identified the HAI cases to assess the epidemiological characteristics of HAIs from January 1, 2018, to December 31, 2021, in a large tertiary hospital in China. Similarly, the trends of HAIs after the COVID-19 outbreak and the seasonal variation of HAIs were further analyzed. Results The HAI cases (n = 7833) were identified from the inpatients (n = 483,258) during the 4 years. The most frequently occurring underlying cause of HAIs was respiratory tract infections (44.47%), followed by bloodstream infections (11.59%), and urinary tract infections (8.69%). The annual prevalence of HAIs decreased from 2.39% in 2018 to 1.41% in 2021 (P = 0.032), with the overall prevalence of HAIs significantly decreasing since the outbreak of COVID-19 (2.20% in 2018–2019 vs. 1.44% in 2020–2021, P

The CLP (Chinese Loess Plateau) is one of the most densely distributed landslides areas. The empirical relationships of the landslides in the CLP remain unclear, and its influencing factors are controversial. According to regional landslide data, this paper studies the relationships and discusses the factors affecting landslides in the CLP. The results show that the area (A) -volume (V) of landslides follows a power law trend described by V = 1.53 A1.19 and the frequency distribution range of H/L (height drop (H)/travel length (L)) is between 0.2 and 1.0, more specifically between 0.2 and 0.4, accounting for 26.1% of the total landslides, indicating that the landslides primarily belong to long run-out landslides. The function of V and H/L of the landslides is followed by H/L = 2.39 V−0.102. About 87% of the landslide is distributed within the equilibrium or mature stages of the watershed. The landslide’s size increases, and the slope of the landslides are steeper with an increase in HI (hypsometric integral). Meanwhile, the loess thickness, human activities, and slope effects on landslides induce landslide occurrence and have positive and negative effects on the landslides within the CLP. With climate change, the risk of landslides will increase in the CLP.

In the present study, the optimization design of the cubic nonlinear damping is conducted for a floating raft isolation system, which can be simplified as a multiple degree-of-freedom system with double parallel freedom inputs. The direct relationship between the power transmissibility and cubic nonlinear damping parameters is derived by taking advantage of the output frequency response function (OFRF) approach. The design requirements are proposed in order to achieve low resonant peak values, low power transmissibility over the high frequency range. The detailed step-by-step design process of the floating raft isolation system applied in a practical vessel is provided. A polynomial function, in terms of the required frequency range, is developed and validated from the simulation data. The case application indicates that the design method determined by the OFRF approach can effectively realize the design requirements of a floating raft isolation system, which can deal with the relationship of the power transmissibility and nonlinear damping parameters.

Multicomponent L12-type material has been shown to be one of the important precipitates used to enhance the properties of high entropy alloys. Its controllability is elusive due to the complexity of the content, which has led to slow progress in the study of their electronic structure. Here, we investigated the deformation mechanism of (Co, Fe, Ni)3Ti-type multicomponent intermetallics using first principles. Thermodynamic parameters, energy and electronic structure suggest that Fe favors a lower γSPF while Ni favors a higher γSPF, which is caused by the difference in the chemical bonding they contribute. The stable outermost electron orbital achieved by Ni-Ti contributes to the good mechanical properties, while the excess lone pair electrons provided by Fe would make the contribution of metallic bonding more significant. Adjustment of the intermetallics-favoring/alloys-favoring element ratio is an effective method to overcome the strength-ductility trade-off. This work provides electronic-level understanding and practical insights to better design and utilize the multicomponent intermetallics enhanced high entropy alloys.

Loess subsurface-erosion refers to the erosion, transport and subsidence of loess caused by surface water infiltration along the dominant seepage channels such as loess macropore joints and fissures. Due to the characteristics of water sensitivity, structural surface development, dominant seepage, etc., loess subsurface-erosion has developed extensively in the loess area, and loess subsurface-erosion has a significant disaster effect, making the mechanism and prevention of loess disasters induced by erosion more complicated. This article first combed the basic concepts of loess subsurface-erosion, based on summarizing the main controlling factors of loess subsurface-erosion, expounded the formation mechanism of loess subsurface-erosion, and expanded the basic connotation of loess subsurface-erosion disaster effect. Finally, according to the current research status of loess submergence, a brief prospect is made for the future research of loess subsurface-erosion, and it is pointed out that more attention should be paid to the research on the key linking role of loess subsurface erosion in the loess disaster chain. This article focuses on the preliminary thinking of several problems in the study of loess subsurface-erosion, and aims to provide scientific suggestions for the subsequent study of loess subsurface-erosion hazard effects.

Due to the topographic conditions, a large number of houses are built on the landslide in the southwest mountainous area, which have potential safety hazard. It is of great significance to explore the action mechanism between landslide and buildings and scientifically guide the design and protection of houses on landslide, so as to ensure the safety of residents' lives and property and promote the harmonious development of people and land. The foundation is the direct object of the landslide on the house. Therefore, taking the masonry structure house foundation as the research object, the deformation characteristics of the foundation in the test and simulation are compared and analyzed by using the method of physical experiment and numerical simulation, the reliability of the boundary setting of the numerical model is verified, and the deformation and failure characteristics of the house foundation under different landslide action modes are studied. The results show that the failure modes of building foundation under the slow deformation of landslide can be summarized into three modes: tension, shear and compression; The location of house crack development is closely related to the location of landslide surface crack. With the increase of the included angle between the main sliding direction of landslide and house foundation, the house foundation damage becomes more and more serious. Therefore, in the site selection and design of houses, priority should be given to the use of landslide extrusion area or reducing the included angle between the central axis of the long side of the house and the main sliding direction of the landslide.

Using bilayer graphene structures (L-type and disk-type structures), we numerically demonstrate a tunable single-band terahertz metamaterial absorber with nearly perfect (100%) absorption by continuously adjusting the graphene Fermi energy parameters to determine the maximum absorption rate, the corresponding center frequency, and bandwidth. Graphene distinct dielectric–metal transition properties make it possible to achieve tunable terahertz absorption. The maximum absorption rate increases from 18% to 100% when the Fermi energy is increased from 0.1 to 1 eV. At 1 eV, the absorption rate exceeds 90% in the range of 0.57–1.03 THz. The incident angle is also tested. When the angle is in the range of 60°, excellent adsorption performance is maintained.

The homojunction provides an effective way to extend the properties of stainless steel, but also leaves more weak points for small atoms to penetrate. In this study, the effects of hydrogen, carbon, and nitrogen atoms at the interface on the austenite/ferrite homojunction were investigated using first principles. This study found that low concentrations of carbon/nitrogen are favorable for the pairing of FCC with BCC compared to hydrogen, which can effectively improve the bonding energy and stability of homogeneous junctions. However, at high concentrations, the interfacial hydrogen can partially act as a mediator for interfacial bonding, which results in a slower decrease in bonding energy. On the contrary, nitrogen causes a sharp decrease in interfacial matching due to excessive strengthening of austenite, which reduces both the binding energy and the stability of the overall system. This study provides valid data and a unique perspective on the development of the austenite/ferrite homojunction.

Loess has a strong water sensitivity, so loess landslides often transform into loess mudflows when water is added on the Chinese Loess Plateau, which results in high casualties and property loss of the Chinese government. In this study, a series of flume tests were designed to study the initiation of loess mudflows. The results reveal that the initiation modes of loess mudflows include large-scale mudflow and retrogressive toe sliding (Type A), and small-scale mudflow and retrogressive toe sliding (Type B). A model was used to analyze the test results that describe the effects of water flow on the potential for hillslope failure and liquefaction. It was found that the soil accumulation was unconditionally stable before a loess mudflow was formed, but as the rainfall continued, the water gradually infiltrated the soil, and the soil accumulation changed from unconditionally stable to unconditionally unstable. Thus, this led to different initiation modes during the tests. For Type A, the water preferentially infiltrated into the area with an uneven density and a large amount of water accumulated. The pore water pressure increased quickly and could not dissipate in time, so the loess liquefied. As the liquefaction area continued to expand and became larger, Type A occurred. Relatively speaking, Type B occurs in soil accumulations with relatively uniform densities. These results provide a certain scientific reference for the study of loess mudflows.

Graphene oxide is an important member of the graphene family which has a wide range of applications. The chemical method, especially the liquid phase method, is one of the most common and important methods for its preparation. However, the complex solution environment not only gives them rich structure, but also brings great challenges for its large-scale industrial synthesis. In order to better realize its industrial application, it is important to understand its structure, such as the source of oxygen-containing functional groups. Here we studied the contribution of four oxygenated acids to oxygen-containing functional groups in Hummers’ method using first principles. We found that the permanganic acid molecules that exist instantaneously due to energy fluctuations can be the source of oxygen-containing functional group. In addition, Stone-Wales defect have a certain effect on the formation of oxygen-containing functional groups, but this effect is not as good as that of solvation effect. This work provides a guide for exploring the source of oxygen-containing functional groups on graphene oxide.

Introduction: Lung cancer is the leading cause of cancer-related morbidity and mortality in the People’s Republic of China. Targeted therapies for patients with lung cancer, which depend on accurate identification of actionable genomic alteration, have improved survival compared with previously available treatments. However, data on the types of molecular testing often used in the People’s Republic of China, and how they have changed over time, are scarce. We explored the overall landscape of molecular testing of lung cancer in mainland People’s Republic of China in the past decade. Methods: We distributed a stratified random sampling survey of molecular testing to 49 hospitals from members of the Molecular Pathology Collaboration Group of Chinese Anti-Cancer Association which was weighted by the numbers of lung cancer cases in seven different geographic regions in mainland People’s Republic of China from 2010 to 2019. The questionnaire contained four parts for all respondents. The questionnaire ascertained the use of approved in vitro diagnostic (IVD) devices published by the Center for Medical Device Evaluation, National Medical Products Administration of the People’s Republic of China. Results: A total of 226,227 NSCLC specimens were tested from 2010 to 2019 in the selected hospitals. The annual number of initiated molecular tests increased over time (p < 0.0001), with an average annual growth rate of 31.8%. A notable increase in the number of molecular tests occurred during 2014 and 2016, which coincided with the approval of the National Medical Products Administration to IVD devices. For the diagnosis of molecular subtypes, EGFR mutation testing was first conducted in year 2007, followed by ALK translocation testing in 2010 and ROS1 in 2011. For other rare genetic variations in NSCLC, BRAF mutation testing was first launched in 2012, MET exon 14 skipping mutation in 2014, HER2 exon 20 mutations in 2017, and RET translocation in 2015. A markedly uneven distribution was also observed in the geography of leading units with the largest number of leading units located in east People’s Republic of China (34.7%, 17 of 49) and the smallest number located in northwest People’s Republic of China (6.1%, 3 of 49). The growth trends we observed illustrate the progress and increasing capability of molecular testing of lung cancer achieved in mainland People’s Republic of China in the decade from 2010. Conclusions: In the decade 2010 to 2019, progress and increased capability of molecular testing of lung cancer were achieved in mainland People’s Republic of China. Further efforts should address the clinical application of next-generation sequencing technology, rare genomic aberrations, and the balance between novel genomic testing techniques and the approval of IVD products.

Lead iodide, PbI2, is one of the promising metal halide materials used for x- and γ-ray detection; it is also a key constituent of organometallic halide perovskites for low-cost solar cells. Here, we report a mature technology for the fabrication of microelectronic devices—an electron beam evaporation method to prepare highly uniform PbI2 thin films with a size of up to 10 cm × 10 cm on various rigid and flexible substrates at room temperature; the fabricated x-ray detectors show a consistent detection performance. The detection performance of the PbI2 thin film based flexible detectors demonstrate high robustness and stability under various bending states, suggesting themselves as potential candidates for the development of next-generation, large-area, and flexible x-ray detecting devices by using pure PbI2 films.

In this study, the applications of the cubic power law damping in vessel isolation systems are investigated. The isolation performance is assessed using the force transmissibility of the vessel isolation system, which is simplified as a multiple-degree-of-freedom system with two parallel freedoms. The force transmissibilities of different working conditions faced in practice are discussed by applying the cubic power law damping on different positions of the vessel isolation system. Numerical results indicate that by adding the cubic power law damping to an appropriate position, the isolation system can not only suppress the force transmissibility over the resonant frequency region but also keep the force transmissibility unaffected at the nonresonant frequency region. Moreover, the design of the nonlinear vessel isolation system is discussed by finding the optimal nonlinear damping of the isolation system.

In this work, we prepared the thermal evaporated amorphous selenium (a-Se) thin films with different evaporation time at low vacuum degree 10-2 Pa. The results showed a-Se thin films were easier to be crystallized with prolonging evaporation time. Also, the transmittance absorption edges of a-Se thin films showed a blue shift with the enhanced optical energy gap from 2.08 eV to 2.15 eV. Further, the dark current was found to depend on energy gap, and became lower as extending evaporation time. Moreover, a-Se thin films showed the improved X-ray photocurrent gain, with a rapid photoresponse and a small applied voltage requirement. Overall, this work revealed that the increase of evaporation time led to better deposition quality of thin films, enhancing energy gap and X-ray photoresponse, but thin films were not able to resist to higher temperature anymore.

Titanium dioxide (TiO2) films have been prepared by DC reaction magnetron sputtering technique on different substrates (glass, SiO2, platinum electrode-Pt, Silicon-Si). X-ray diffraction (XRD) patterns showed that all TiO2 films were grown along the preferred orientation of (110) plane. Samples on Si and Pt substrates are almost monophasic rutile, however, samples on glass and SiO2 substrates accompanied by a weak anatase structure. Atomic force microscopy (AFM) images revealed uniform grain distribution except for films on Pt substrates. Photoluminescence (PL) spectra showed obvious intrinsic emission band, but films on glass was accompanied by a distinct defect luminescence region. Raman spectroscopy suggested that all samples moved to high wavenumbers and films on glass moved obviously.

The performance of dye-sensitized solar cells (DSSC) depends strongly on the electrolyte. In this paper, the electrolytes with various solvents and different potassium iodide (KI) & iodine (I2) concentration were prepared and their influence on the DSSC performance were investigated. The results revealed DSSC with electrolyte prepared by organic solvent show better performance than that of inorganic solvent. Meanwhile, the increasing of KI concentration from 0.1 to 0.6 mol/L can effectively improve the short-circuit current density (Jsc) from 0 2, correspondingly, the DSSC conversion efficiency (η) increased from 0.04% to 0.11%. On the other hand, the Jsc and η of DSSC increased firstly then decreased with the I2 concentration raised from 0.025 mol/L to 0.125 mol/L. It is worth to notice that the open-circuit voltage (Voc) of DSSC is almost unchanged with the concentration of KI and I2. In this paper, the best performance DSSC (Jsc=0.87 mA/cm2, Voc=0.57 mV, η=0.23%) can be obtained with electrolyte at a KI and I2 concentration of 0.6 mol/L and 0.075 mol/L respectively. Finally, the electrolytes used water and mixture of acetonitrile & ethylene glycol as solvents showed the latter presented better stability after setting at room temperature for 72 hours.

The ZnO thin films have been prepared by sol-gel method at different annealing temperatures and aging time. The structural properties of ZnO thin films were investigated by X-ray diffraction (XRD) patterns and atomic force microscope (AFM) images. The results indicated that the film possess a hexagonal wurtzite structure with preferred orientation along the (002) direction. The crystalline quality of films improved with increasing post-annealing temperature, while gradually worsened with prolonging aging time. The optical properties of ZnO thin films were studied by the ultra-violet transmittance (UV-Vis) and photoluminescence (PL) spectra. The variations of UV-Vis transmittance and energy gap accorded well with the tendency presented in XRD patterns and AFM images. The PL spectra appeared the apparent ultraviolet emission and visible emissions. As the annealing temperature increased, the ultraviolet and visible emissions of films enhanced and decreased respectively. However, as the sol aging time prolonged, the PL emission presented an opposite tendency.

Mega-earthquakes that occur in mountainous areas of densely populated cities are particularly catastrophic, triggering large landslides, destroying more buildings, and usually resulting in significant death tolls. In this paper, earthquake scenarios in the Guyuan Region of China are used as an example to study earthquake disaster risk assessment and a method of assessment is proposed that uses the peak ground acceleration (PGA), landslides triggered by the earthquake, and the effects on the population. The method is used to develop scenarios for earthquake disaster risk assessment along the Haiyuan and Liupanshan Faults for earthquake magnitudes of Ms 7.0, 7.5, 8.0, and 8.5 triggered by one of the two faults. The quantitative earthquake disaster risk maps in the study area were developed by integrating the values of the at-risk elements for the earthquake factor, population, and landslide hazard. According to the model results, the high-hazard zone was mainly located in the severely affected areas along the faults and on the western side of the faults. These results can be useful for emergency preparation planning, response plans, and resource assessment.