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Note on Redshift Distortion in Fourier Space

Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 51-62页

作者： Yan-Chuan Cai jun pan Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We explore features of redshift distortion in Fourier analysis of N-body simulations. The phases of the Fourier modes of dark matter density fluctuation are generally shifted by the peculiar motion along the line of sight, the induced phase shift is stochastic and has a probability distribution function （PDF） that is symmetric about the peak at zero shift and whose exact shape depends on the wave vector, except on very large scales where phases are invariant by linear perturbation theory. Analysis of the phase shifts motivates our phenomenological models for the bispectrum in redshift space. Comparison with simulations shows that our toy models are very successful in modeling bispectrum of equilateral and isosceles trian- gles at large scales. In the second part we compare the monopole of the power spectrum and bispectrum in the radial and plane-parallel distortion to test the plane-parallel approximation. We confirm the results of Scoccimarro that difference of power spectrum is at the level of 10%, and, in the reduced bispectrum, the difference is as small as a few percent. However, on the plane perpendicular to the line of sight of kz = 0, the difference in power spectrum be- tween the radial and plane-parallel approximation can be more than - 10%, and even worse on very small scales. Such difference is prominent for bispectrum, especially for configura- tions of tilted triangles. Non-Ganssian signals under the radial distortion on small scales are systematically biased downside than are in the plane-parallel approximation, with amplitudes depending on the opening angle of the sample point to the observer. This observation gives warning to the practice of using the power spectrum and bispectrum measured on the kz = 0 plane as estimates of the real space statistics.

关键词： cosmology theory-large-scale structure of universe-methods statistical

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Relativistic transformation between τ and TCG for Mars missions under IAU Resolutions

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Research in Astronomy and Astrophysics 2014年第2期14卷 233-240页

作者： jun-Yang pan Yi Xie Department of Astronomy Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education

Considering the fact that the general theory of relativity has become an in- extricable part of deep space missions, we investigate the relativistic transformation between the proper time of an onboard clock τ and the Geocentric Coordinate Time （TCG） for Mars missions. By connecting τ with this local timescale associated with the Earth, we extend previous works which focus on the transformation between τ and the Barycentric Coordinate Time （TCB）. （TCB is the global coordinate time for the whole solar system.） For practical convenience, the relation between τ and TCG is recast to directly depend on quantities which can be read from ephemerides. We find that the difference between τ and TCG can reach the level of about 0.2 seconds in a year. To distinguish various sources in the transformation, we numerically calculate the contributions caused by the Sun, eight planets, three large asteroids and the space- craft. It is found that if the threshold of 1 microsecond is adopted, this transformation must include effects due to the Sun, Venus, the Moon, Mars, Jupiter, Saturn and the velocities of the spacecraft and Earth.

关键词： reference systems -- time -- method: numerical -- space vehicles

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Metagenomic analysis on resistance genes in water and microplastics from a mariculture system

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Frontiers of Environmental Science & Engineering 2022年第1期16卷 77-89页

作者： jian Lu jun Wu jianhua Wang CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China Yantai Research Institute Harbin Engineering UniversityYantai 264006China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Microplastics existing widely in different matrices have been regarded as a reservoir for emerging *** systems have been observed to host microplastics and antibiotic resistance genes(ARGs).However,more information on proliferation of ARGs and metal resistance genes(MRGs)in mariculture system at the presence of microplastics is *** study used metagenomic analysis to investigate the distribution of ARGs and MRGs in water and microplastics of a typical mariculture *** 18 types including 174 subtypes of ARGs were detected with the total relative abundances of 1.22/1.25 copies per 16S rRNA copy for microplastics/*** resistance genes were the dominant ARGs with the abundance of 0.35/0.42 copies per 16S rRNA copy for microplastics/*** intI1 was dominant gene among 6 detected mobile genetic elements(MGEs)with the abundance of 75.46/68.70 copies per 16S rRNA copy for water/*** 9 types including 46 subtypes of MRGs were detected with total abundance of 5.02×10^(2)/6.39×10^(2)copies per 16S rRNA copy for water/microplastics while genes resistant to copper and iron served as the dominant ***,Bacteroidetes,and Actinobacteria accounted for 84.2%/89.5%of total microbial community in microplastics/*** with relatively high abundance were significantly positively related to major genera,MGEs,and *** in mariculture system could enrich most of MRGs and some ARGs to serve as potential reservoir for these *** findings of this study will provide important information on resistance gene pollution at presence of microplastics in the mariculture system for further proposing suitable strategy of environmental management.

关键词： Antibiotic resistance genes Metal resistance genes Metagenomic analysis Microplastics Mariculture

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Effect of gastric fluid on adsorption and desorption of endocrine disrupting chemicals on microplastics

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Frontiers of Environmental Science & Engineering 2022年第8期16卷 193-205页

作者： Jie Wu jian Lu jun Wu CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China University of Chinese Academy of Sciences Beijing 100049China Yantai Research Institute Harbin Engineering UniversityYantai 264006China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Microplastics and endocrine disrupting chemicals are emerging pollutants in the marine environment because of their potential *** effect of gastric fluid on the adsorption and desorption of 17β-estradiol(E2)and 17α-ethynylestradiol(EE2)to microplastics was *** adsorption and desorption isotherms of E2/EE2 on microplastics could be well fitted by the Freundlich model while the Gibbs free energy of these processes were negative,proving that the reaction occurred spontaneously on the heterogeneous surface of the *** ratios of EE2(55%–59%)on PVC were larger than that of E2(49%–55%)to indicate that EE2 was less stable in gastric fluid,which could be explained by the fact that the hydrophobicity of EE2 was greater than E2.E2/EE2 were more easily desorbed from PVC in the gastric fluid and the desorption amount(5.25–12.91/7.19–17.86μg/g)increased by 2.51 times in comparison with that in saline solution(2.22–7.81/2.87–10.80μg/g).The decrease of pH and the increase of ionic strength in gastric fluid could further strengthen desorption of E2/EE2 from *** promotion of gastric juice on desorption of PVC was achieved by reducing the hydrophobicity of the PVC *** desorption rate of E2/EE2 at 18°C and 38°C was respectively 44%–47%/46%–50%and 49%–55%/56%–59%,indicating that PVC loaded with E2/EE2 had a relatively greater risk of releasing pollutants in the gastric fluid of constant temperature marine organisms while higher temperatures exposed higher hazards for variable temperature *** interaction between microplastics and pollutants might be mainly hydrophobic interaction.

关键词： Microplastics Gastric fluid Endocrine-disrupting chemicals Adsorption Desorption

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Removal of steroid hormones from mariculture system using seaweed Caulerpa lentillifera

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Frontiers of Environmental Science & Engineering 2022年第2期16卷 1-11页

作者： jian Lu Cui Zhang jun Wu CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Yantai Research Institute and Graduate School Harbin Engineering UniversityYantai 265501China

The removal of steroid hormones from the mariculture system using seaweeds(Caulerpa lentillifera,Ulva pertusa,Gracilaria lemaneiformis,and Codium fragile)was *** results illustrated that both 17β-estradiol(E_(2))and 17α-ethinylestradiol(EE_(2))could be removed by the seaweeds at different levels,and the Caulerpa lentillifera was the most efficient *** than 90%of E_(2) or EE_(2) at concentration of 10μg/L was removed by Caulerpa lentillifera within 12 *** including initial quick biosorption,the following slow accumulation,and biodegradation might explain the removal mechanisms of E_(2)/EE_(2) by Caulerpa lentillifera.E_(2)/EE_(2) removal was positively related to the nutrient level and the initial concentration of steroid hormone.A significant linear relationship for E_(2) and EE_(2) existed between the initial pollutant concentration and the average removal *** highest removal kinetic constant(k)value was obtained at 30℃as 0.34/h for E_(2) and at 20℃as 0.28/h for EE_(2),demonstrating the promising application potential of Caulerpa lentillifera in the water purification of the industrialized mariculture system with relatively high water *** and efficient removal of E_(2) and EE_(2) by Caulerpa lentillifera was still achieved after 3 cycles in the pilot-scale *** steroid hormones and nutrients in mariculture wastewater could also be simultaneously removed using Caulerpa *** findings demonstrated that Caulerpa lentillifera was the promising seaweed for the removal of steroid hormones in mariculture systems.

关键词： Phycoremediation Steroid hormones Seaweed Mariculture Caulerpa lentillifera

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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

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Interpretation of Chinese Expert Consensus on the Diagnosis and Management Strategy of Patients with Statin Intolerance: A guiding file for helping to lipid management for Chinese population

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Journal of Geriatric Cardiology 2024年第7期21卷 713-715页

作者： jian-jun LI Cardiometabolic Center National Center for Cardiovascular DiseaseChinese Academy of Medical ScienceFuwai HospitalBeijingChina

It is well-known that elevated low-density lipoprotein cholesterol(LDL-C)is a causal risk factor for atheroscler-otic cardiovascular disease(ASCVD),statins are cornerstone drugs for the cause-based treatment of ASCVD,which has created a new era for ASCVD ***,statin intolerance is not clinically uncommon,which there are several issues with confu-sion and ***,a file named Chinese Expert Consensus on the Diagnosis and Management Strategy of Pa-tients With Statin Intolerance,like a navigator,has recently been published written by a team of experts from the Cardiovascular Metabolic Medicine Professional Committee,Expert Committee of the National Center for Cardiovascular Diseases aiming to en-hance the standardized clinical application of statins and improve the prevention and clinical *** this article,author briefly summarized the key points of above consensus in order to helping to comprehending the content of the consensus sugges-tions.

关键词： Expert Strategy corners

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Optical monitoring of the Seyfert galaxy NGC 4151 and possible periodicities in its historical light curve

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Research in Astronomy and Astrophysics 2014年第8期14卷 923-932页

作者： Di-Fu Guo Shao-Ming Hu jun Tao Hong-Xing Yin Xu Chen Hong-jian pan Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesSchool of Space Science and PhysicsShandong University Shanghai Astronomical Observatory Chinese Academy of Sciences

We report B, V and R band CCD photometry of the Seyfert galaxy NGC 4151 obtained with the 1.0m telescope at Weihai Observatory of Shandong University and the 1.56 m telescope at Shanghai Astronomical Observatory from 2005 December to 2013 February. Combining all available data from literature, we have constructed a historical light curve from 1910 to 2013 to study the periodicity of the source using three different methods （the Jurkevich method, the Lomb-Scargle periodogram method and the Discrete Correlation Function method）. We find possible periods of P1 = 4 ± 0.1,/92 = 7.5 ±0.3 and P3 = 15.9± 0.3 yr.

关键词： methods data analysis -- galaxies: active -- galaxies individual (NGC 4151)

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Structural dynamic responses analysis applying differential quadrature method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1831-1838页

作者： PU jun-ping ZHENG jian-jun College of Architecture and Civil Engineering Zhejiang University of Technology Hangzhou 310032 China

Unconditionally stable higher-order accurate time step integration algorithms based on the differential quadrature method (DQM) for second-order initial value problems were applied and the quadrature rules of DQM, computing of the weighting coefficients and choices of sampling grid points were discussed. Some numerical examples dealing with the heat transfer problem, the second-order differential equation of imposed vibration of linear single-degree-of-freedom systems and double-degree-of-freedom systems, the nonlinear move differential equation and a beam forced by a changing load were computed, respectively. The results indicated that the algorithm can produce highly accurate solutions with minimal time consumption, and that the system total energy can remain conservative in the numerical computation.

关键词： Differential quadrature method (DQM) Dynamic response analysis Conservation of energy

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Adsorption and desorption of steroid hormones on saline soil

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 177-190页

作者： Jie Wu jian Lu jun Wu CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China University of Chinese Academy of Sciences Beijing 100049China Yantai Research Institute Harbin Engineering UniversityYantai 264006China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Soil organic matter content was the main driving factor affecting adsorption and desorption process of 17β-estradiol(E2)and 17α-ethynylestradiol(EE2)on saline *** adsorption and desorption of E2 and EE2 on three saline soils showed the similar behavior that soil with the highest organic content possessed the highest adsorption capacity and the lowest desorption capacity for E2 and *** adsorption capacity of untreated soil samples(with organic matter)was larger than that of soil samples without organic *** soil with the largest adsorption capacity,adsorption capacity of E2/EE2 on the untreated soil and soil colloid(with organic matter)respectively reached 0.15/0.30μg/g and 0.16/0.33μg/g while the soil and soil colloid without organic matter hardly adsorbed *** adsorption capacity of E2/EE2 at the initial concentration of 100μg/L was 25/15 times higher than that at the initial concentration of 5μg/L.E2 and EE2 had the same adsorption sites on saline soil while EE2 possessed higher competition intensity for adsorption sites than ***-first-order model(R^(2)=0.995–0.986)and Langmuir model(R^(2)=0.989–0.999)could better fit the adsorption process of E2 or *** thermodynamic study further showed that the adsorption of E2/EE2 on saline soil was a spontaneous exothermic *** desorption capacity of EE2/E2 accounted for 40%/78%of the total adsorption capacity to possibly exert potential risk to the *** variation of the salinity led to the variation of soil organic carbon which subsequently changed the adsorption and desorption behaviors of endocrine disrupting chemicals in coastal saline *** study provides a new insight on the interfacial behavior of endocrine disrupting chemicals on saline soil.

关键词： Saline soil Steroid hormones Adsorption Desorption Soil organic matter

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