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underground laboratories · Deep underground observation ·Scientific questions—Insights from observations of multi-physic fields in deep underground labs

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Science China Earth Sciences 2025年

作者： Huiqi REN Yun WANG Chang CHEN Guangyu Fu longqing QIu lianghui GuO Chengliang XIE Yongsheng HE heping SuN Jiwen TENG Institute of Defense Engineering Academy of Military Sciences State Kay laboratory of Geological Processes and Mineral Resources Key Laboratory of Intraplate Volcanoes and Earthquakes Ministry of Education China University of Geosciences (Beijing) Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

This paper presents a comprehensive review on recent development and research conducted in domestic and international.underground laboratories. We first introduce the differences in three environments—surface, mountain tunnel cavities and underground coal mine tunnels—by examining cosmic ray background, ambient noises related to gravity and seismic measurement, and electromagnetic noises in magnetic and magnetotel.uric measurements. We highlight potential misuse of the term underground lab or Deep underground lab when describing observations in different physical fields. We introduce unique features of underground coal mine tunnels in China, such as large spaces, ultra-quiet conditions, and ultra-clean environments. When comparing with mountain tunnel cavities and borehole observations, coal mine tunnel observations have superior long-term stability and high precision. Through observations and comparisons of multi-physic fields at surface and the deep underground, we find that the higher SNR seismic observations conducted in deep underground tunnels in coal mines are beneficial to improve velocity tomography of the solid earth. The gravity observation with a Superconducting Quantum Interference Device(SQuID) makes it possibly to capture slow earthquake, which has not been observed previously in the Chinese mainland. SQuID magnetic observations can detect fluctuations as weak as femto-Tesla(fT), enabling us to explore the attenuation of Schumann Resonance down to the solid Earth. This opens opportunities to investigate the connections between the Earth's magnetic field and the interactions within the human brain and heart. To improve the precision of quantum measurement,we should consider the possible effects of weak magnetic disturbances in deep underground environments. Finally, we discuss the importance of deep underground laboratories, observing facilities and techniques deployed in these laboratories, and their possible connection with respect to “deep space” an

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Childhood malaria in the Niger delta area of Nigeria:mothers/care givers'perception,definition and treatment practices

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Asian Pacific Journal of Tropical Medicine 2009年第3期2卷 52-58页

作者： Idogun E.Sylvester Airauhi l.u Department of Chemical Pathology University of Benin Teaching HospitalBenin City Department of Medical Microbiology Biology University of Benin Teaching HospitalBenin City

Objective:The objective of the study was to evaluate mothers/care givers perception of malaria,their treatment practices and the effects on the outcome of ***:Four hundred and sixty children were enrolled and their mothers/care givers *** children were screened for malaria parasitaemia and there after,blood specimens were obtained for biochemical and haematological evaluation from those children who met the criteria and tested positive to *** *** cell volume,electrolytes,urea, creatinine,plasma glucose,and serum bilirubin were ***:A total of 460 children were studied, 233(50.7%) males and 227(49.3%) *** malaria cases were 112(24.3%) and severe malaria 348(75.7%).Those who presented early 106(23.0%) and those who presented late 354(77.0%).Perception and definition of malaria as well as the treatment seeking behaviors vary significantly with the level of education of the mothers and care *** without formal education 68(51.9%) wrongly perceived that the etiology of malaria can only be diagnosed by native doctors compared to those with primary six education 61 (26.5%) and junior secondary education 10(10.1%).Only 43(9.3%) gave the correct dose of chloroquine syrup to their sick children,while 32(7.0%) gave at sub optimal ***:Wrong perception of malaria especially the complicated malaria and wrong treatment practices are major contributory factors to the high mortality and morbidity of malaria in *** is therefore a need for health education to correct the wrong ideas about the cause and treatment practices of malaria as part of malaria control programme.

关键词： Childhood malaria Mothers/Caregivers Perception and treatment practices Nigeria

Restriction Theorems on Métiver Groups Associated to Joint Functional Cal.ulus

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Chinese Annals of Mathematics,Series B 2018年第6期39卷 1017-1032页

作者： heping l.u An ZHANG Department of Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China CEREMADE Universite Paris-DauphinePlace du Marechal de Lattre de Tassigny75775 Paris Cedex 16France

The authors get on Metivier groups the spectral resolution of a class of operators m（l, -Δ）, the joint functional cal.ulus of the sub-laplacian and laplacian on the centre, and then give some restriction theorems together with their asymptotic estimates, asserting the mix-norm boundedness of the spectral projection operators Pμ^m for two classes of functions re（a, b） =（a^α＋b^β）^γ or （1＋a^α＋b^β）^γ,with α,β〉0,γ≠0.

关键词： Restriction operator Metivier group Functional cal.ulus

Bilinear Riesz means on the Heisenberg group

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Science China Mathematics 2019年第12期62卷 2535-2556页

作者： heping l.u Min Wang School of Mathematical Sciences Peking University

In this article, we investigate the bilinear Riesz means Sα associated with the sublaplacian on the Heisenberg group. We prove that the operator Sαis bounded from lp1 × lp2 into lp for 1 p1, p2 ∞ and1/p = 1/p1 + 1/p2 when α is larger than the suitable smoothness index α（p1, p2）. There are some essential differences between the Euclidean space and the Heisenberg group for studying the bilinear Riesz means *** use some special techniques to obtain lower indices α（p1, p2）.

关键词： Heisenberg group bilinear Riesz means restriction theorem

Feasible synthesis of porous h-BN by Mg^(2+)induced lattice dislocations for hydrogen and ammonia storage

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Nano Research 2025年第1期18卷 94-99页

作者： Xiaojia Huang Zihao Wang Yihan Kong li Jiang Baolin Wang Jiangtao Jia heping Ma Guangshan Zhu Key laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China School of Chemical Engineering and Technology Xi’an Jiaotong university Xi’an 710049China

Hexagonal boron nitride(h-BN)is a two-dimensional(2D)layered material with a structure similar to graphite and it has potential as a hydrogen and ammonia storage ***,dense packing in the standard h-BN structure limits its surface area and prevents the B and N from being adsorption *** this study,the addition of Mg^(2+)during h-BN synthesis facilitated the growth of lattice dislocations and led to a crosslinked three-dimensional(3D)porous structure.A proposed formation mechanism for porous h-BN was confirmed by several characterization routes,most clearly by high-resolution transmission electron microscopy(HRTEM).Porous Mg/BNs exhibited high H_(2)and NH_(3)uptakes and showed potential for H_(2)and NH_(3)storage.

关键词： hexagonal boron nitride porous material dislocation gas storage

A lINEAR IM PlICIT ll-lEGENDRE GAlERKIN CHEBYSHEV COllOCATION M ETHOD FOR GENERAlIZED TIME- AND SPACE-FRACTIONAl BuRGERS EQuATION

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Journal of Computational Mathematics 2019年第5期37卷 629-644页

作者： Yubo Yang heping Ma Nanhu College Jiaxing UniversityJiaxing 314001 China Department of Mathematics Shanghai UniversityShanghai 200444China

In this paper, a linear implicit ll-legendre Galerkin Chebyshev collocation method for the generalized time-and space-fractional Burgers equation is developed. A linear implicit finite difference scheme based on the l 1-algorithm for the Caputo fractional derivative is proposed for temporal discretization. And the legendre Galerkin Chebyshev collocation method, based on the legendre-Galerkin variational form, but the nonlinear term and the right-hand term are treated by Chebyshev-Gauss interpolation, is proposed for spatial discretization. Rigorous stability and convergence analysis are developed. Numerical examples are shown to demonstrate the accuracy, stability and effectiveness of the method.

关键词： Generalized fractional Burgers equation Stability and convergence analysis legendre Galerkin Chebyshev collocation method Finite difference method

THE PRElIMINARY STuDY ON lANDSCAPE Cul.uRE ORIENTATION AND EXPlOITATION OF THE SOuTH DONGTING lAKE WETlAND

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Chinese Geographical Science 2002年第3期12卷 254-261页

作者： heping WANGBao－zhong CentralSouthForestryuniversity Zhuzhou412006P.R.China ChinaInternationalEngineeringConsultingCorporation Beijing100044P.R.China

Dongting lake is internationally a n important *** studied and s ummarized the conception,func-tion,classification and current situation of the wetland-landscape cu l.ure in this *** results showed that the cul-ture of Dongting lake wetland was ric h in diversity,which are the Rice Cul tivation Cul.ure,high-balustrade dwelling,Nuo Cul.ure,Ship Cul.ure,Dragon Bo at Cul.ure,Chu Cul.ure,Ancient Arc hitecture landscape,Wetland Foodstuff and Cuisine Cul.ure,Civil Art,Historic Heritage and Cul.ural Relics,Revolutionary Sites and Ruins,and Production and living Cul.ure,*** also evaluated the eco-tourism value of wetland l andscape cul.ure,and analyzed its f eatures and *** results revealed t hat the south Dongting lake wetland p lays a key role on the Changjiang(Yangtze)River reaches civilization and Chinese civilization,even has great influence on the global *** summ arized that the soul of the south Dongting lake Cul.u re was Wetland Cul.ure,Water Cul.ur e,Rice Cultivation and Chu *** thoughts,principles and approaches of sustainable exploitation and ut ilization of the wetland landscape c ul.ure were formulat-ed and suggested.

关键词： south dongting lake wetland landscape landscape cul.ure eco-tourism wetland cul.ure

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metal.urgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling lü Chunchi Zhang Dong liang lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

A restriction theorem for Grushin operators

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Frontiers of Mathematics in China 2016年第2期11卷 365-375页

作者： heping l.u Manu SONG School of Mathematical Sciences Peking University Beijing 100871 China School of Natural and Applied Sciences.Northwestern Polyteehnical.university Xi'an 710129 China

We study the Grushin operators acting on Rx d1× Rt d2 and defined by the formula l -∑ j d1=1 xj-∑ j d1=1｜xj｜2 ∑ k d2=1 2 tk. We establish a restrictiontheorem associated with the considered operators. Our result is an analogue of the restriction theorem on the Heisenberg group obtained by D. Muller [Ann. ofMath., 1990, 131： 567-587].

关键词： Grushin operator scaled Hermite operator restriction operator