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With the increasingly harsh global environment, the new energy industry has received strong support from national policies. On this basis, the enthusiasm of relevant departments and enterprises for the new energy industry has increased. This paper discusses the development of new energy vehicles by analyzing the development status, market development prospects and limitations of new energy vehicles. In addition, we conduct a corresponding valuation analysis of BYD Automobile, which is a leader in the new energy vehicles of China. According to the analysis, the intrinsic value of BYD's stock will be lower than its stock value, indicating that the investment value is higher perceived at this stage. As a consequence, the investment in BYD nowadays ought to be reduced in the future. These results shed light on offering better understanding of the development status and limitations of new energy vehicles, as well as providing a guideline for investment evaluation of the industry.

Diverse transformations of 2-alkylthiobenzamides have been established to synthesize 2,3-dihydrobenzothiazin-4-ones, benzoisothiazol-3-ones and 2-alkylthiobenzonitriles in the presence of Selectfluor.

The electrocatalytic urea oxidation reaction (UOR) can be utilized as an alternative anodic reaction for water electrolysis to provide more economic electrons and high-efficiency H2 production.

High entropy alloys (HEAs) are promising as multifunctional electrocatalysts owing to their inherent compositional and structural complexity and thus the multiple active sites for different reactions.

Objective: This study is aimed to design wearable care equipment based on the narrow-band Internet of Things (NB-IoT) to assist in applying health-related big data and gain the optimum treatment time for patients with fractures. Methods: A wearable care equipment based on the NB-IoT technique (namely, a brace) was designed by combining sensors with embedded systems, man–machine interaction technique, and so on. Also, the exercise heart rate, the surface temperature of disease location, and the data on oxyhemoglobin saturation of patients were acquired using sensors. Next, these data were sent to an application (APP) on a cell phone after transmission to a single-chip machine for processing. Finally, the data on heart rate, body temperature, blood oxygen, and their variation curves were displayed on the APP. Results: The wearable care equipment could provide a normal average recovery curve for patients with fractures, which was instrumental for patients and doctors to fully grasp the rehabilitation condition. If the key indicators were abnormal and exceeded the threshold value, the wearable equipment generated an early warning signal to alert patients to seek medical attention in time. Conclusions: The test results indicated that the wearable care equipment based on the NB-IoT technique could realize the acquisition, storage, and analysis of the physiological parameters of patients. The wearable equipment had a series of characteristics, including low cost, low power dissipation, stable signal connection, and strong practicability, having a certain practical significance for the consistency of enhancing the health service and assisting the health-related big data development.

In this paper, we aim to identify the significant variables that contribute to the injury severity level of the person in the car when an accident happens and build a statistical model for predicting the maximum injury severity level as well as estimating the potential economic cost in a car accident based on those variables. The General Estimates System data, which is a representative sample of police-reported motor vehicle crashes of all types collected by the National Highway Transportation Safety Administration, from the years 2012 to 2013 is the main data source. Some other data sources such as the car safety rating from the United State Department of Transformation and the state-specific cost of crash deaths fact sheets are also used in the predictive model building process. An interactive system programmed in HyperText Markup Language, Cascading Style Sheets and JavaScript is developed based on the results of predictive modeling. The system is hosted on a website at http://gessmu.azurewebsites.net for public access. The system allows users to input variables that are significant contributors in car accidents and obtain the predicted maximum injury severity level and potential economic cost of a car accident.

Fipronil (FP) is an emerging insecticide which could induce reproductive toxicity in male rats at very low dosage, but the occurrence of FP and its transformation products (FPs) in human seminal plasma and their impacts on human semen quality have not been documented. In this study, FPs including FP, fipronil desulfinyl (FP-DES), fipronil sulfone (FP-SFO), fipronil amide (FP-AM), and fipronil sulfide (FP-SFI), were measured in seminal plasma samples (n = 200), which were collected from Shijiazhuang, north China. The cumulative concentration of FPs (ΣFPs), in the seminal plasma samples ranged from 0.003 to 0.180 ng/mL (median: 0.043 ng/mL). FP-SFO was the major target analyte (median: 0.040 ng/mL), accounting for approximately 42.3-100.0% of the ΣFPs. Significantly higher exposure levels of FPs were found in the overweight or obese group (≥25 kg/m

Numerous studies have examined the association between long-term exposure to particulate matter with an aerodynamic diameter of ≤2.5 μm (PMConsidering the limitations of previous meta-analyses and the publication of many new studies in recent years, we conducted this meta-analysis to assess the relationship between long-term PMWe searched PubMed, Web of Science, Embase, and Scopus for relevant studies published until April 2, 2021 and reviewed the reference lists of previous reviews. A total of 28 observational studies reporting RR or OR with 95% CI for the association between long-term PMAfter the sensitivity analysis, we excluded one study with a high degree of heterogeneity, resulting in 27 studies and 28 independent reports. Approximately 42 million participants were involved, and the cases of hypertension in cohort and cross-sectional studies were 508,749 and 1,793,003, respectively. The meta-analysis showed that each 10 μg/mA significantly positive correlation was observed between long-term PM

A perinatal high-salt (HS) diet was reported to elevate plasma triglycerides. This study aimed to investigate the hypothesis that a perinatal HS diet predisposed offspring to non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of abnormal lipid metabolism, and the possible mechanism. Female C57BL/6 mice were fed a control diet (0.5% NaCl) or HS diet (4% NaCl) during pregnancy and lactation and their offspring were sacrificed at weaning. The perinatal HS diet induced greater variation in fecal microbial beta-diversity (β-diversity) and increased bacteria abundance of Proteobacteria and Bacteroides. The gut microbiota dysbiosis promoted bile acid homeostasis disbalance, characterized by the accumulation of lithocholic acid (LCA) and deoxycholic acid (DCA) in feces. These alterations disturbed gut barrier by increasing the expression of tight junction protein (Tjp) and occludin (Ocln), and increased systemic lipopolysaccharide (LPS) levels and hepatic inflammatory cytokine secretion (TNF-α and IL-6) in the liver. The perinatal HS diet also inhibited hepatic expression of hepatic FXR signaling (CYP7A1 and FXR), thus triggering increased hepatic expression of pro-inflammatory cytokines (TNF-α and IL-6) and hepatic lipid metabolism-associated genes (SREBP-1c, FAS, ACC), leading to unique characteristics of NAFLD. In conclusion, a perinatal HS diet induced NAFLD in weanling mice offspring, the possible mechanism was related to increased bacteria abundance of Proteobacteria and Bacteroides, increased levels of LCA and DCA in feces, and increased expressions of hepatic FXR signaling.

This paper proposed a nano-watt voltage reference circuit was implemented in a 0.18um CMOS process with trim techniques. In order to reduce power consumption, a MOS-Only Voltage Reference is presented, which is based on the threshold voltage, However, the deviation of Vref because of process variation is large. We use the difference of Vth instead of Vth to improve the stability of output voltage at different process corner. The simulation results show that under 27°C and 0.5V supply voltage, the output reference voltage is 236mV, the temperature coefficient is 30.8 ppm/°C over temperature range of 125°C (-40°C to 85°C) and only consume 5.5nW at 0.5V supply voltage.

This paper presents a sub-wavelength moth-eye-like antireflective structure on lithium triborate (LiB3O5, LBO) surface that can effectively promote the transmittance and maintain high laser-induced damage threshold (LIDT). Fabricated by holographic lithography and reactive ion-beam etching techniques, sub-wavelength periodic arrays can be obtained on the crystal surface. The surface morphology and transmittance were measured with atomic force microscope and spectrophotometer respectively. Single-sided transmittance of the LBO with moth-eye-like structure was confirmed to exceed 98% in the wavelength range of 1028–1300 nm, while is 98.73% at 1064 nm. For 1064 nm laser with the pulse width of 12 ns, the measured 1-on-1 LIDT is 42.57 J/cm2, which is about 2.28 times that of LBO compared with traditional antireflection (AR) coatings.

Chilling requirement is an important agronomic trait of peach and other deciduous fruit trees. It is a quantitative indicator of natural dormancy and its release in a low temperature environment. It is directly related to the distribution area of fruit trees and the success of cultivation. Therefore, chilling requirement evaluation is very important for cultivar breeding and plant introduction. The existing evaluation method has obvious disadvantages such as harsh conditions, complex operation and time-consuming, which greatly prolong the evaluation process. Chilling requirement of peach floral buds could be quickly estimated by a portable E-nose (PEN3.5). The ratio R of the actual accumulated chilling hours during any period of the dormancy and release process to the chilling requirement was used to indicate the stage of chilling accumulation. 5 stages were set as the R value was 0 (StageⅠ), 0.4 (Stage Ⅱ), 0.8 (Stage Ⅲ), 1.0 (Stage Ⅳ) and 1.2 (Stage Ⅴ). Volatile compounds from the floral buds of 9 cultivars with known chilling requirements at the five stages were tested, and the signals of 10 types of sensors were different. Broad-methane gradually decreased during the dormancy process, and reached the bottom at dormancy release, with a significant difference in each stage (p 0.05). It proved that the model established in this paper can be used to evaluate the chilling requirement of peach floral buds. This is the first time that E-nose detection and PLSR quantitative analysis model are combined to be used in the estimation of chilling requirements and have achieved efficient and convenient evaluation. It has a high potential to be applied in the evaluation of peach chilling requirements in the future. And for other deciduous fruit trees or plants, the innovative method is of great reference significance.

Hydrophobic antireflective coating is fabricated by physical vapor deposition. The optical, contact angle and laser damage resistance properties are investigated, respectively. The transmittance of the antireflective coating with hydrophobic layer is 99.58% at 1064 nm with normal incidence. The contact angle with water is 115.6[Formula: see text]. The laser damage threshold of the zero probability is 22 J/cm2 at 1064 nm with the 12 ns pulse width. This new hydrophobic antireflective coating can be applied in the areas of astronomical optics, laser medical equipment and solar energy, etc.

The Quaternary Qigequan Formation, a continental clastic sedimentation system in Sanhu Depression of eastern Qaidam Basin, west-central China, contains abundant biogenic gas resources. Favorable characteristics of the Sanhu Depression’s geological history and framework responsible for biogenic gas production include rapid sedimentation, shallow burial depth, organic-rich sediments, high porosity/permeability, and a saline depositional environment. Gases are dominated by methane (>99%), with trace ethane/propane (C2+3

To investigate the incidence and prevalence of developmental odontogenic cysts in children and adolescents and compare the features of the two most common types, dentigerous cyst and keratocystic odontogenic tumor (KCOT).A retrospective review in a series of 369 patients with all histological diagnoses of developmental odontogenic cysts in children (≤12 years) and adolescents (13-18 years) was conducted.Among these, 361 (97.8%) patients were diagnosed as dentigerous cyst (n = 281) and KCOT (n = 80), with the male-to-female ratios of dentigerous cyst and KCOT both being 2:1. The average age of the patients with KCOT was older than that of those with dentigerous cyst (14.7 years vs 11.8 years, p0.001). Dentigerous cyst (59.1%) was more common in children, but KCOT (78.8%) was more common in adolescents (p0.001). Dentigerous cyst (57.6%) predominantly located on the maxilla, but KCOT (60.3%) predominantly located on the mandible (p = 0.010).Adolescent patients with lesions located on the mandible would favor KCOT over dentigerous cyst. This study aids in better knowledge of the prevalence of developmental odontogenic cysts in a large pediatric population, and shows that a well-supported early diagnosis is indispensable for a more adequate treatment.

With the progress of voltage source converter (VSC) technology, VSC-HVDC system is becoming a promising solution to renewable energy access. To address the problem of power control when renewable energy parallels in the power grid through VSC-HVDC, a direct power control method is proposed for VSC-HVDC system. First, the architecture of VSC-HVDC system is introduced. Then a direct power control method is presented to meet the characteristics of renewable energy (i.e. randomness, volatility and uncontrollability). Moreover, the operational characteristics of the HVDC system under different conditions were analyzed by numerical simulation based on PSIM. Finally, a 10kw VSC-HVDC prototype system was developed, and the experimental results validate the effectiveness of the proposed power control method.

Quaternary biogenic gas fields in the Sanhu area of the Qaidam Basin are characterized by gentle structures, shallow burial, weak compaction, high porosity and great bulk thickness, which determine their unique geophysical anomalies, such as the locally low gravity, micro-magnetic high frequency anomaly, seismic event push-down and attribute anomaly. An integrated geophysical processing and interpretation scheme is put forward for shallow biogenic gas prediction in this area. Amplitude preservation is performed for 1:100000 gravity data and the processing results are correlated with known gas distributions and aeromagnetic results, remote sensing and seismic hydrocarbon detection. This study shows that the residual gravity low anomaly has a good correlation with the gas field and, as an important feature of the biogenic gas field, the amplitude of residual gravity low anomaly is directly proportional to the measure of gas reservoir. Based on the residual gravity low anomaly and other exploration data, the distribution of gas reservoirs in the Sanhu area is characterized by vertical overlapping, lateral zoning and local enrichment. Residual gravity anomaly, in combination with regional geologic data, reveals three favorable zones, one fairly favorable zone (low gas production zone), five possibly favorable zones and four favorable targets. Key words: Qaidam Basin, Sanhu area, Quaternary, biogenic gas, gravity, magnetic, seismic, geophysical integration, exploration direction

Several giant biogenic gas fields (with proven gas reserves greater than 25 billion cubic meters) have been discovered in recent years in the Sanhu area of eastern Qaidam Basin. This area has an average surface altitude of around 2800 m, and forms the northern segment of the Qinghai-Tibet Plateau. The biogenic gas fields occur mostly within or adjacent to the depocenter of approximately 3400 m of Quaternary sediments. The gas reservoirs, with burial depth generally less than 1900 m, are unconsolidated sandstones with approximately 24–40% porosity, and are interbedded with mudstones containing on average 0.3% TOC. The occurrence of methanogens in the shallow Quaternary sediments appears to depend on both the sedimentary facies and burial depths, thus most of the biogenic gases in the Sanhu area appears to have derived from the source kitchens in the central sag above a biogenic gas floor at the depth around 1800 m. The key gas system elements for the formation of the giant biogenic gas accumulations include (1) secular low surface temperatures and lake water hypersalinity favor the preservation of suitable organic substrates for biogenic methane generation, (2) well-developed sand and mud interbeds, (3) sufficient cumulative thickness of water-saturated mudstones as caprocks, (4) presence of syndepositional anticlines of Pleistocene and later age, (5) a regional hydrogeological system favoring northeastward gas migration, and (6) ongoing dynamic gas migration and accumulation with abundant gas supply.

This study provided an overview of the geological setting and geochemical characteristics of the Pleistocene shallow gas accumulations in the eastern Qaidam Basin, NW China. The five largest gas accumulations discovered in this region have a combined enclosure area of about 87 km 2 and 7.9 trillion cubic feet (tcf) of proven gas reserves. The dominance of methane (mostly more than 99.9%) and the δ 13 C and δ D values of methane (−68.51 to −65.00‰ and −227.55 to −221.94‰, respectively) suggest that these gases are biogenic, derived from the degradation of sedimentary organic matter by methanogens under relatively low temperatures ( 15% TDS) and strong stratification. The deposition and extensive lateral occurrence of lacustrine – shoreline sands/silts in beach sand sheets and sand bars provided excellent reservoirs for the biogenic gas generated from adjacent rocks. Effective but dynamic gas seals are provided by a combination of factors, such as the intermittent vertical variation in the sediment lithologies, hydraulic trapping due to the mudstone water saturation, the hydrocarbon gradient created as the result of gas generation from potential caprocks, and the presence of a regional caprock consisting of 400–800 m of muds and evaporites. It appears that the most favorable traps for large gas accumulations occur on structural slopes near the major gas kitchen, and the prolific gas pools are often those large gentle anticlines with little faulting complication.

Quaternary biogenic gas reservoirs in Sanhu area of Qaidam Basin, China are featured by gentle structure, shallow burial, weak formation compaction, high porosity and large thickness, which determine their unique geophysical anomalies. Amplitude preservation processing of 1:100,000 gravity data and correlation with Tainan and Sebei-1 gas fields are carried out. Study shows that local low gravity corresponds to biogenic gas reservoir and local low residual gravity is an important geophysical characteristic of shallow biogenic gas reservoir. It is presented that Sanhu gas reservoirs distribution are featured by vertical overlapping, lateral zoning and local enrichment.