Acid deposition critical loads modeling for the simulation of sulfur exceedance and reduction in Guangdong, China

The current acid deposition critical loads in Guangdong, China were calculated using the PROFILE model with a 3 km × 3 km resolution. Calculations were carded out for critical loads of potential acidity, actual acidity, sulfur and nitrogen, with values in extents of 0-3.5, 0-14.0, 0-26.0 and 0-3.5 kmol/（hrnE.year）, respectively. These values were comparable to previously reported results and reflected the influences of vegetation and soil characteristics on the soil acid buffering capacity. Simulations of SO2 emission and sulfur deposition in this study showed that sulfur deposition core areas mirrored SO2 emission centers. The prediction of sulfur deposition after 20% and 40% reduction of SO2 emission suggested that the reduction of area sources contributed greatly to the decrease of sulfur deposition. Thus, abatement of area source emissions could be the primary way to mitigate sulfur deposition in Guangdong to meet both the provincial and national regulations of air pollution control.

Joint asymptotic distribution of exceedances point process and partial sum of stationary Gaussian sequence

Let {Xi}i=1^∞ be a standardized stationary Gaussian sequence with covariance function τ（n） =EX1Xn＋1, Sn =∑i=1^nXi,and X^-n=Sn/n.And let Nn be the point process formed by the exceedances of random level （x/√2 log n＋√2 log n-log（4π log n）/2√log n） √1-τ（n） ＋ X^-n by X1,X2,…, Xn. Under some mild conditions, Nn and Sn are asymptotically independent, and Nn converges weakly to a Poisson process on （0,1].

On the Exceedance Probabilities of Extreme Drift Motions of An Offshore Structure

The response statistics of a compliant offshore structure excited by slowly varying wave drift forces is calculated by use of a numerical path integral solution method. The path integral solution is based on the Ganss-Legendre interpolation scheme, and the values of the response probability density are obtained at the Gauss quadrature points in sub-intervals. It is demonstrated that a distinct advantage of the path integral solution is that the joint probability density of the response displacement and velocity is one of the by products of the calculations. This makes it possible to calculate the mean level up-crossing rates, which provides estimates of the exceedance probabilities of specified response levels for given time periods.

Discussion on the Relationship between “Anti-great Earthquakes” and Ground Motion with a Low Probability of Exceedance

In this paper we discuss the differences and relationship between"great earthquakes",rare ground motion,and very rare ground motion.Taking the Beichuan-Yingxiu potential seismic source zone in Longmenshan seismic belt as an example,we revealed the relationship between the effects of"great earthquakes"and rare ground and very rare ground motion.After pointing out scientific and technical problems in the current seismic fortification system,we suggest that very rare ground motion should be considered if we want to deduce the potential hazard of great earthquakes in the future.

Levels of Probability of Exceedance for Current Code Spectra in China

Long-period acceleration spectra determined by seismic safety evaluation for project sites are generally lower than that given by relative code spectra.In this paper,we discuss the recurrence periods corresponding to the code spectra of different periods,by using ground motion attenuation laws for sites of types Ⅰ and Ⅲ.We show the results that the longer the periods of code spectra are commonly the more conservative the seismic level is.As for the project examples in this paper,when the periods are longer than 3.7 or 5.2 seconds for sites of types Ⅰ or Ⅲ,the recurrence periods corresponding to the code spectra are longer than 5000 years.We suggest that some problems need to be further discussed,including the reliability of the present attenuation laws,the performance of those project structures that suffer long period seismic waves and have been designed according to the conservative codes,and the effects of ground motion parameters such as velocity and displacement on seismic design.

The Relationship Among Bedrock Seismic Ground Motion Parameters with Different Exceedance Probabilities in the Panxi Area

Based on the calculation of the bedrock effective peak acceleration (EPA) zoning map in the Panxi area, the ratios of EPA with exceedance probabilities of 63%, 5%, 3%, 2% and 1% over 50 years to that of 10% in 50 years are 0.302, 1.30, 1.55, 1.76 and 2.14, respectively. The seismic effect will be conservative and safe if taking this zoning map as the earthquake resistant fortification level and following the relevant rules of the Code for Seismic Design of Buildings (GBJ11 89) to calculate the seismic effect. Furthermore, the main factors that influence the A10/A63 ratios have been found to be the attenuation relationship of seismic ground motion, the division of seismic potential source regions and the seismicity parameters. These achievements are helpful to the spreading and applying of the zoning map.

Probability Distribution Characteristics of Strong Nonlinear Waves Under Typhoon Conditions in the Northern South China Sea

The generation and propagation mechanism of strong nonlinear waves in the South China Sea is an essential research area. In this study, the third-generation wave model WAVEWATCH Ⅲ is employed to simulate wave fields under extreme sea states. The model, integrating the ST6 source term, is validated against observed data, demonstrating its credibility. The spatial distribution of the occurrence probability of strong nonlinear waves during typhoons is shown, and the waves in the straits and the northeastern part of the South China Sea show strong nonlinear characteristics. The high-order spectral model HOS-ocean is employed to simulate the random wave surface series beneath five different platform areas. The waves during the typhoon exhibit strong nonlinear characteristics, and freak waves exist. The space-varying probability model is established to describe the short-term probability distribution of nonlinear wave series. The exceedance probability distributions of the wave surface beneath different platform areas are compared and analyzed. The results show that with an increase in the platform area, the probability of a strong nonlinear wave beneath the platform increases.

A METHODOLOGICAL STUDY ON AMH COPULA-BASED JOINT EXCEEDANCE PROBABILITIES AND APPLICATIONS FOR ASSESSING TROPICAL CYCLONE IMPACTS AND DISASTER RISKS(PART Ⅰ)

A disaster induced by a tropical cyclone(TC)is a complex non-linear process,involving interactions of multiple factors.Assuming that the resilience to TC disasters remains basically unchanged,the disaster-causing risk is usually consistent with intensities of the TC-induced rainstorms and wind.When an area is hit by a low probability TC,the rainstorm and wind intensities are higher,and the likelihood for causing a disaster is greater.Therefore,criteria for the impact of a TC and disaster risk assessments can be established based on the probable intensities of the TC-associated rainstorms and wind.In this study,an AMH Copula-based function is introduced to investigate the joint risk probabilities of TC rainstorms and wind.In line with the equivalence principle of the distribution of a stochastic atmospheric phenomenon in both time and space,and taking the impact on Shanghai of TC Haikui as an example,the Copula-based joint probability distribution model is developed to assess the impacts of TC rainstorms and wind,based on the marginal distributions of the maximum daily rainfall and extreme gust velocity.The joint exceedance probabilities of TC rainstorms and wind derived from the model can be used as criteria to measure the risk levels.As our findings show,this approach captures the TC risks well,especially in high-risk areas.The aim of the study is to provide a practically useful concept for making more accurate assessments of the risk level of an extreme weather event using observational data,and objective criteria for risk avoidance and transfer.

Joint Limit Distributions of Exceedances Point Processes and Partial Sums of Gaussian Vector Sequence

In this paper, we study the joint limit distributions of point processes of exceedances and partial sums of multivariate Gaussian sequences and show that the point processes and partial sums are asymptotically independent under some mild conditions. As a result, for a sequence of standardized stationary Gaussian vectors, we obtain that the point process of exceedances formed by the sequence （centered at the sample mean） converges in distribution to a Poisson process and it is asymptotically independent of the partial sums. The asymptotic joint limit distributions of order statistics and partial sums are also investigated under different conditions.

Harnessing the power of pericytes and hypoxia-inducible factor-1 to modulate stroke outcome

The human brain has exceedingly high metabolic demands.The cerebral vasculature has the critical task of providing sufficient blood supply to meet this demand.The sudden interruption of blood flow to the brain,as observed during ischemic stroke,results in acute neurological injury with devastating consequences-a high rate of adult disability and death.Ischemic stroke is thus a vascular disorder with a dramatic neurological impact.There is an urgent need for more effective disease management to combat stroke as current treatment paradigms,focusing on vascular recanalization and neuroprotection,have only limited clinical success.Since accumulating data suggests successful long-term neuroprotection is unlikely to be achievable without a functional microvascular network,strategies that reduce endothelial dysfunction could be indispensable.Encouragingly,very recent evidence highlighted herein suggests protecting the humble pericyte may be a new approach to reaching this goal.

A statistical study on the correlation between sporadic Ca+layer and Es in Beijing(40.5°N,116°E)

From April 2020 to June 2022,a Ca+lidar with dual-wavelength and narrow-band emitting lasers utilizing all-solid-state technology was employed to conduct observations in Beijing(40.41°N,116.01°E)for a total duration of 1797.79 hours over 280 nights.A total of 286 sporadic Ca+layers were observed,with heights ranging from 88 to 120 km and densities varying from 5.33 to 2200 cm^(-3).We simultaneously observed the ionosonde,located 28 km from the lidar,and found a correlation of 61.89%between the sporadic Ca+layer and the sporadic E layer.When the sporadic Ca+layer has a downward phase trend,there is a correlation of 76.84%.By excluding the influence of ionosonde sensitivity,we focus only on calcium ions that have a density exceeding 140 cm^(-3),which exhibit a correlation of82.25%.Above 100 km,the correlation significantly increases,reaching approximately 90%.Furthermore,the correlation between the sporadic Ca+layer and the sporadic E layer is particularly noticeable during the summer season,reaching around 90%.This phenomenon can be attributed to the variations in metal ions that occur during different seasons.

Current Status of Brazil’s New Energy and Green Low-carbon Practices in Deep-water Oil Fields

Brazil possesses abundant new energy resources such as solar energy,wind energy,and biomass energy,and is at the forefront of the world in the development and utilization of new energy,becoming a pioneer in energy transition and low-carbon development.Renewable energy accounts for nearly half of Brazil’s primary energy consumption,with the share in the power sector exceeding 75%.Brazil has achieved its carbon peak and is still actively promoting carbon and emission further reduction and the development of new energy.

Ten Changes in the Cosmetics Industry in 2023

New life was accompanied by death,consumption upgrading was accompanied by consumption downgrading,triumphant advancement was accompanied by steady retreatin.In 2023,magic realist dramas were played in China’s cosmetics industry one after another.That year,the domestic brands set off a prologue of counterattacking foreign brands with“Proya winning the first place in Tmall’s Double Eleven promotion for 2023”as a landmark event.That year,South Korean cosmetics,Japanese cosmetics and major European and American brands“became depressed”collectively,and the acutely turbulent list could hardly conceal the injury of“being defeated”and“being unsalable”.That year,Proya and Botanee achieved a rapid growth,and the first domestic cosmetics group with the annual operating revenue exceeding 8.0 billion yuan was coming into being.

Current Status and Prospects of China’s Natural Gas Industry

In 2023,China’s natural gas sector experienced robust growth in both supply and demand dynamics,as consumption regained an upward trend,reaching 394.53 billion m3,reflecting a 7.6%year-on-year surge.Domestic gas production and reserves persistently progressed,hitting a production volume of 228.84 billion m3 and achieving a seven-year consecutive increment exceeding 10 billion m^(3).After an initial sharp decline,imported natural gas rebounded to record growth;the combined import volume of pipeline gas and LNG climbed to 163.92 billion m^(3),a notable 11.3%rise compared to the previous year.As China’s policies for stable economic growth are further entrenched in 2024,the macroeconomic recovery is anticipated to continue.Bolstered by the dual-carbon strategy and the transformative policies targeting high-energy-consuming industries,the natural gas market is expected to sustain its rapid expansion,with estimated growth in demand ranging between 5.8%and 7.1%.

On Cloud Nine Karamay's leading AI-empowered cloud computing

The benchmark of Xinjiang's computing power is determined by Karamay,known as an"oil city."With an impressive annual crude oil output exceeding 16 million tons,Karamay is now exploiting computing power,the"new black gold"of the artificial intelligence (AI) era.Since the Karamay Cloud Computing Industrial Park officially opened in 2013,it has attracted more than 150 companies including three that are publicly listed on the New Third Board.

SCIENCE AND TECHNOLOGY

Deep-Earth Borehole Drilling Project Achieves 10,000-Meter Milestone China has achieved a significant breakthrough in deep-Earth exploration with the drilling of a superdeep borehole in Xinjiang Uygur Autonomous Region exceeding the 10,000-meter mark,making it the deepest vertical well in Asia,even though the project as a whole is not yet completed.Amid the continuous humming of the drilling rig,the number on an electronic screen in the command center reached the milestone of 10,000 meters at 2:48 p.m.on March 4.More than 100 workers on site,who had eagerly anticipated this moment,erupted into cheers.Located in the hinterland of the Taklimakan Desert in the Tarim Basin,Shenditake 1 is a scientific exploratory borehole with a designed depth of 11,100 meters.In addition to searching for oil and gas resources,it is also tasked with pursuits such as exploring the evolution of Earth.

In Brief

The annual oil and gas output of Fuman Oilfield,China's largest ultra-deep oilfield,exceeded 4 million tons,On December 29,2023,the annual oil and gas production of Fuman Oilfield,China's largest ultra-deep oilfield,exceeded 4 million tons,reaching a new peak of 4.036 million tons.This marks another new advancement in the large-scale and efficient development of ultra-deep and complex oil and gas reservoirs in CNPC Tarim Oilfield,creating a new growth pole for increasing reserves and production of crude oil in China.Fuman Oilfield is the oilfield with the largest number of ultra-deep wells of over 8,000 meters in China,and more than 110 wells have a depth exceeding 8,o00 meters and are defined as Underground Everest".In 2019,the annual oil and gas production of Fuman Oilfield increased from 20,000 tons at the beginning of development to 1.08 million tons.

Machine-learning-assisted Investigation into the Relationship between the Built Environment,Behavior,and Physical Health of the Elderly in China

Due to an increasing life expectancy and decreasing fertility rate,China officially entered a stage of increased ageing in 2011[1].According to China’s seventh national census,2019,the country’s overall population was 1.44 billion,and this included eighteen per cent of people over 60(13.5%of people exceeding 65 years old).

Spin Transport Properties of MnBi_(2)Te_(4)-Based Magnetic Tunnel Junctions

The van der Waals heterojunctions,stacking of different two-dimensional materials,have opened unprecedented opportunities to explore new physics and device concepts.Here,combining the density functional theory with non-equilibrium Green’s function technique,we systematically investigate the spin-polarized transport properties of van der Waals magnetic tunnel junctions(MTJs),Cu/MnBi_(2)Te_(4)/MnBi_(2)Te_(4)/Cu and Cu/MnBi_(2)Te_(4)/hBN/n·MnBi_(2)Te_(4)/Cu(n=1,2,3).It is found that the maximum tunnel magnetoresistance of Cu/MnBi_(2)Te_(4)/hBN/3·MnBi_(2)Te_(4)/Cu MTJs can reach 162.6%,exceeding the system with only a single layer MnBi_(2)Te_(4).More interestingly,our results indicate that Cu/MnBi_(2)Te_(4)/h-BN/n·MnBi_(2)Te_(4)/Cu(n=2,3)MTJs can realize the switching function,while Cu/MnBi_(2)Te_(4)/h-BN/3·MnBi_(2)Te_(4)/Cu MTJs exhibit the negative differential resistance.The Cu/MnBi_(2)Te_(4)/h-BN/3·MnBi_(2)Te_(4)/Cu in the parallel state shows a spin injection efficiency of more than 83.3%.Our theoretical findings of the transport properties will shed light on the possible experimental studies of MnBi_(2)Te_(4)-based van der Waals magnetic tunneling junctions.

乘势而上:中国斡旋沙特伊朗复交及其影响

On March 10,2023,China,Saudi Arabia and Iran issued a trilateral joint statement in Beijing,in which Saudi Arabia and Iran agreed to resume their diplomatic relations and reopen their embassies and missions within a period not exceeding two months.The Saudi-Iran confrontation has been one of the most intractable regional conflicts in the Middle East.The announcement of the two countries to restore their diplomatic ties resulted from the interplay of several favorable factors and is expected to set off a series of positive developments that might de-escalate many regional hotspot issues in Yemen,Syria,Iraq,and Lebanon.