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Torsion Fields Generated by the Quantum Effects of Macro-bodies

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research in Astronomy and Astrophysics 2022年第12期22卷 335-343页

作者： Da-Ming chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We generalize Einstein's General Relativity(GR)by assuming that all matter(including macro-objects)has quantum *** appropriate theory to fulfill this task is Gauge Theory Gravity(GTG)developed by the cambridge *** is a“spin-torsion”theory,according to which,gravitational effects are described by a pair of gauge fields defined over a flat Minkowski background *** matter content is completely described by the Dirac spinor field,and the quantum effects of matter are identified as the spin tensor derived from the spinor *** existence of the spin of matter results in the torsion field defined over *** field plays the role of Bohmian quantum potential which turns out to be a kind of repulsive force as opposed to the gravitational potential which is *** equivalence principle remains and essential in this theory so that GR is relegated to a locally approximate theory wherein the quantum effects(torsion)are *** a toy model,we assume that the macro matter content can be described by the covariant Dirac equation and apply this theory to the simplest radially symmetric and static gravitational ***,by virtue of the cosmological principle,we are led to a static universe model in which the Hubble redshifts arise from the torsion fields.

关键词： cosmology:theory (cosmology:)dark matter (cosmology:)dark energy

On Harmonic Maps between Generalized Flag Manifolds

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Acta Mathematica Sinica,English Series 1992年第1期8卷 1-16页

作者：候自新 Department of Mathematics Nankai University Tianjin 300071China

The theory of harmonic maps has been developed since the 1960’s(see[2]).In recentyears,some authors discussed the harmonicity of"homogeneous"maps between Riemannianhomogeneous spaces using the theory of Lie *** G and G′ be compact Lie groups,Hand H′ their closed subgroups *** that a homomorphism θ:G→G′maps H into H′; then there exists an induced map fθ:G/H→G′/H′.*** gave anecessary and sufficient condition for such a map to be harmonic,when G/H and G′/H′ aregeneralized flag manifolds,H=T is a maximal torus and G′ is a unitary group; and he gavesome interesting examples(see[3]).We generalize his results to the case of general generalizedflag manifolds G/H,i.e.H is a centralizer of a torus,and give some new examples of harmonicmaps.

关键词： Oc On Harmonic Maps between Generalized Flag Manifolds maps

Tetrabromobisphenol A(TBBPA): A controversial environmental pollutant

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Journal of Environmental Sciences 2020年第11期32卷 54-66页

作者： Hui Zhou Nuoya Yin Francesco Faiola State key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China college of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Tetrabromobisphenol A(TBBPA)is one of the most widely used brominated flame retardants and is extensively used in electronic equipment,furniture,plastics,and *** is frequently detected in water,soil,air,and organisms,including humans,and has raised concerns in the scientific community regarding its potential adverse health *** exposure to TBBPA is mainly via diet,respiration,and skin *** in vivo and in vitro studies based on animal and cell models have demonstrated that TBBPA can induce multifaceted effects in cells and animals,and potentially exert hepatic,renal,neural,cardiac,and reproductive ***,other reports have claimed that TBBPA might be a safe *** this review,we re-evaluated most of the published TBBPA toxicological assessments with the goal of reaching a conclusion about its potential *** concluded that,although low TBBPA exposure levels and rapid metabolism in humans may signify that TBBPA is a safe chemical for the general population,particular attention should be paid to the potential effects of TBBPA on early developmental stages.

关键词： Tetrabromobisphenol A(TBBPA) Developmental toxicity Endocrine disrupting chemicals(EDc) Hepatotoxicity Neurotoxicity

4 × 20 GHz silica-based AWG hybrid integrated receiver optical sub-assemblies

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chinese Optics Letters 2018年第6期16卷 29-33页

作者： chaoyi Li Junming An Jiashun Zhang Liangliang Wang Jianguang Li Yue Wang Xiaojie Yin Hongjie Wang Yuanda Wu State key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China college of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100049 China

Both the 4 × 20 GHz coarse wavelength division multiplexing and LAN-WDM receiver optical sub-assemblies（ROSAs） were developed. The ROSA package was hybrid integrated with a planar lightwave circuit arrayed waveguide grating（AWG） with 2% refractive index difference and a four-channel top-illuminated positive-intrinsicnegative photodetector（PD） array. The output waveguides of the AWG were designed in a multimode structure to provide flat-top optical spectra, and their end facet was angle-polished to form a total internal reflection interface to realize vertical coupling with a PD array. The maximum responsivity of ROSA was about 0.4 A/W, and its 3 dB bandwidth of frequency response was up to 20 GHz for each transmission lane. The hybrid integrated ROSA would be a cost-effective and easy-assembling solution for 100 Gb E data center interconnections.

关键词： WDM AWG GHz silica-based AWG hybrid integrated receiver optical sub-assemblies LAN

Discovery of New Thioviridamide-Like compounds with Antitumor Activities

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chinese Journal of chemistry 2019年第10期37卷 1015-1020页

作者： Yuqing Li Jingyu Liu Haoyu Tang Yanping Qiu Dandan chen Wen Liu The education Ministry key Lab of Resource chemistry and Shanghai key Laboratory of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China State key Laboratory of Bioorganic and Natural Products chemistry Center for Excellence on Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of Sciences345 Lingling RoadShanghai 200032China Huzhou center of Bio-Synthetic Innovation 1366 Hongfeng RoadHuzhouZhejiang 313000China

Thioviridamide is a structurally unique compound with potent antitumor *** biosynthesis of thioviridamide follows a typical pathway as ribosomally synthesized and post-transiationally modified peptides,making the genome mining-based discovery of thioviridamide-like compounds *** advantage of the linkage between the precursor peptide and the metabolite skeleton,we identified a new biosynthetic gene cluster in Streptomyces *** S-87 that could encode thioviridamide *** of the whole gene cluster led to the isolation and structure elucidation of TVA-YJ-4 and TVA-YJ-5,two novel thioviridamide-like compounds featuring N-terminal capping *** screening of the fermentation extracts also detected TVA-YJ-6,another new thioviridamide-like compound with representative methionine *** analysis further revealed that these structural modifications were introduced during the compound extraction process instead of through genuine enzymatic ***-YJ-4 and TVA-YJ-5 display slightly reduced cytotoxic activities against a panel of tumor cell lines in comparison with their parental natural product,*** work will expand the membership of this rare class of compounds and promote related biosynthetic studies.

关键词： cluster linkage rational

Monovalent cation perm-selective membranes(McPMs)"New developments and perspectives

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chinese Journal of chemical Engineering 2017年第11期25卷 1606-1615页

作者： Liang Ge Bin Wu Dongbo Yu Abhishek N.Mondal Linxiao Hou Noor U1 Afsar Qiuhua Li Tingting Xu Jibin Miao Tongwen Xu cAS key Laboratory of Soft Matter chemistry Collaborative Innovation Center of Chemistry for Energy MaterialsSchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

As one of the most typical and promising membrane processes, electrodialysis(ED) technique plays a more and more significant role in industrial separation. Especially, the separation of monovalent cations and multivalent cations is currently a hot topic, which is not only desirable for many industries but also challenging for academic explorations. The main aim of the present contribution is to view the advances of a wide variety of monovalent cation perm-selective membranes(McPMs) and their preparation technologies including(1) covalent crosslinking,(2) surface modification,(3) polymer blending,(4) electrospinning,(5) nanofiltration alike membrane,and(6) organic–inorganic hybrid. The relevant advantages and disadvantages with respect to some specific cases have been discussed and compared in detail. Furthermore, we elaborately discuss the opportunities and challenges of McPMs, the fabricating strategies to take and the future perspectives.

关键词： Ion exchange membranes Monovalent cation perm-selective membranes Electrodialysis Ion separation Electro-nanofiltration

Transcriptome analysis elucidates key changes of pleon in the process of carcinization

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Journal of Oceanology and Limnology 2021年第4期39卷 1471-1484页

作者： Ya’nan YANG Zhaoxia cUI Tianyi FENG chenchang BAO Yuanfeng XU School of Marine Sciences Ningbo UniversityNingbo 315832China

When megalopa molting to the first juvenile crab stage,the crabs undergo carcinization *** study the key physiological and morphological processes in carcinization,we performed a comparative transcriptomic analysis between the cephalothoraxes and the pleons of megalopa and the first juvenile crab stage in chinese mitten *** results reveal that the major physiological and morphological changes in the pleon were related to energy metabolism(oxidative phosphorylation and AMPk pathways),ventral nerve cord fusion(apoptosis-related pathways),and metamorphosis(transcription factors,Hedgehog and Hippo pathways).We also discovered that the key Hox genes abdominal-B and abdominal-A might regulate morphological changes,especially in the degeneration of the fifth pair of pleopods,and ganglion fusion,*** the regulatory mechanisms of carcinization may help us better understand the developmental biology of the juvenile crabs.

关键词： Eriocheir sinensis carcinization pleon physiology morphology

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN chunyan1, HUANG Yunjie1, LI Jinghong1,2 & cHEN Shaowei3 1. State key Laboratory of Electroanalytical chemistry, changchun Institute of Applied chemistry, chinese Academy of Sciences, changchun 130022, china 2. Department of chemistry, Tsinghua University, Beijing 100084, china 3. Department of chemistry, University of california, Santa cruz, Santa cruz, cA 95064, USA State key Laboratory of Electroanalytical chemistry changchun Institute of Applied chemistry Chinese Academy of Sciences Changchun China Department of chemistry Tsinghua University Beijing China Department of chemistry University of California Santa Cruz Santa Cruz USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPcs) as elec-tron-transfer mediators. 3-Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPcs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPcs act as diffusing elec-tron-mediators and electron transfers to and from the MPcs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPcs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

Attack on Optical Double Random Phase Encryption Based on the Principle of Ptychographical Imaging

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chinese Physics Letters 2016年第1期33卷 63-66页

作者：李拓史祎诗 college of Material Science and Opto-Electronic Technology University of Chinese Academy of Sciences Academy of Opto-electronics Chinese Academy of Sciences

The principle of ptychography is applied in known plain text attack on the double random phase encoding （DRPE） system. We find that with several pairs of plain texts and cipher texts, the model of attack on DRPE can be converted to the model of ptyehographical imaging. Owing to the inherent merits of the ptyehographical imaging, the DRPE system can be breached totally in a fast and nearly perfect way, which is unavailable for currently existing attack methods. Further, since the decryption keys can be seen as an object to be imaged from the perspective of imaging, the ptychographical technique may be a kind of new direction to further analysis of the security of other encryption systems based on double random keys.

关键词： of as for it Attack on Optical Double Random Phase Encryption Based on the Principle of Ptychographical Imaging in is on