检索结果-南通市图书馆

Constraints on holographic QCD phase transitions from PTA observations

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

A New Type of Bistable Switching in Two-Dimensional Nonlinear Optical Superlattices

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第2期13卷 109-112页

作者： wang zhen-lin YANG zhen-ju MIN Nai-ben National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

we investigate theoretically optical responsc in a two-dimensional optical superlattice with Kerr-type *** ind that in addition to the bistability reported in ***.71(1993)1003 by Xu et,al.,a new type of bista ble switching behavior *** bistability is based on the occurrence of the stop gap in the lincar spectraand the nonlinear mechanism on it,which makes switching between transmitting and non-transmitting states achievable.

关键词： Nonlinear addition nonlinear

Removal of nitrogen and phosphorus in a combined A^2/O-BAF system with a short aerobic SRT

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2006年第6期18卷 1082-1087页

作者： DING Yong-wei wang lin wang Bao-zhen wang zheng School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China School of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

A bench-scale anaerobic/anoxic/aerobic process-biological aerated filter （A^2/O-BAF） combined system was carded out to treat wastewater with lower C/N and C/P ratios. The A^2/O process was operated in a short aerobic sludge retention time （SRT） for organic pollutants and phosphorus removal, and denitrification. The subsequent BAF process was mainly used for nitrification. The BAF effluent was partially returned to anoxic zone of the A^2/O process to provide electron acceptors for denitrification and anoxic P uptake. This unique system formed an environment for reproducing the denitdfying phosphate-accumulating organisms （DPAOs）. The ratio of DPAOs to phosphorus accumulating organisms （PAOs） could be maintained at 28% by optimizing the organic loads in the anaerobic zone and the nitrate loads into the anoxic zone in the A^2/O process. The aerobic phosphorus over-uptake and discharge of excess activated sludge was the main mechanism of phosphorus removal in the combined system. The aerobic SRT of the A^2/O process should meet the demands for the development of aerobic PAOs and the restraint on the nitrifiers growth, and the contact time in the aerobic zone of the A^2/O process should be longer than 30 min, which ensured efficient phosphorus removal in the combined system. The adequate BAF effluent return rates should be controlled with 1--4 mg/L nitrate nitrogen in the anoxic zone effluent of A^2/O process to achieve the optimal nitrogen and phosphorus removal efficiencies.

关键词： nitrogen and phosphorus removal denitrifying phosphorus removal denitrifying phosphorus accumulating organisms (DPAOs) anaerobic/anoxic/aerobic process (A^2/O) biological aerated filter (BAF) aerobic sludge retention time (SRT)

Polyaniline Nanofibrils Array Synthesized within the Anodic Aluminum Oxide Template

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2001年第9期12卷 743-846页

作者： zhen wang Hu lin LI Department of Chemistry Lanzhou UniversityLanzhou 730000

Polyaniline (PANI) nanofibrils were prepared within the anodic aluminum oxide (AAO) template. The surface appearance of PANI nanofibrils and the structure of nanofibril array were observed by scanning electron microscopy (SEM). The diameter and the length of PANI nanofibrils are dependent on the pore diameter and the thickness of AAO template. X-ray photoelectron spectroscopy (XPS) supplies the surface analysis confidence on the PANI nanofibrils. Fourier Transmission Infrared (FTIR) was used to confirm the fibrils composed of PANI.

关键词： Polyaniline scanning electron microscopy X-ray photoelectron spectroscopy

使用Fabry—Perot干涉腔稳频的GaAlAs激光器(英文)

在线全文

学校读者我要写书评

暂无评论

计量学报 1989年第1期 15-17页

作者：吴欣欣王德沛谢麟振王义遒北京大学无线电电子学系

GaAlAs激光器的激射频率被锁定于Fabry-Perot干涉腔上。在锁定之后其激射频率的涨落已被大大地降低。所测得的频率稳定度（对Fabry-Perot干涉腔中心频率的跟踪稳定度）如下:其中第1个稳频系统为5×10-12（1s）、1.5×10-12（10s）、1.2... 详细信息

GaAlAs激光器的激射频率被锁定于Fabry-Perot干涉腔上。在锁定之后其激射频率的涨落已被大大地降低。所测得的频率稳定度（对Fabry-Perot干涉腔中心频率的跟踪稳定度）如下:其中第1个稳频系统为5×10-12（1s）、1.5×10-12（10s）、1.2×10-12（100s）;而第2个稳频系统为8×10-12（1s）、2×10-12（10s）、1.8×10-12（100s）。

关键词：干涉腔 Perot GaAlAs Fabry 激光器光激射器电子器件

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan zheng Qingming lin Yan You zheng Gong Yangping Zhuang Jiali Wu Yu wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

在线全文

学校读者我要写书评

暂无评论

粉煤灰制备纳米氧化铝的工艺研究

安徽化工 2017年第1期43卷 30-32页

作者：王安顺李广学王震林伟王培根安徽理工大学化学工程学院安徽淮南232001

以粉煤灰为原料,经焙烧、热酸溶、结晶后与Na_2CO_3反应,制备出纳米级Al_2O_3,产物经激光粒度分析仪、X射线衍射仪等方法进行表征和定性测定,分析出粉煤灰制备纳米氧化铝的最佳条件。

关键词：粉煤灰纳米氧化铝最佳条件

Transcriptome analysis of the Antarctic psychrotrophic bacterium Psychrobacter sp. G in response to temperature stress

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2017年第2期36卷 78-87页

作者： wang zhen LI Yang lin Xuezheng The First Institute of Oceanography Key Laboratory of Marine Bioactive Substances State Oceanic Administration Qingdao 266061 China

The key functional genes involved in temperature adaption of the Antarctic psychrotrophic bacterium Psychrobacter sp. G. were identified by transcriptomic sequencing. We analyzed the global transcriptional profile of Psychrobacter sp. G under cold stress（0°C） and heat stress（30°C）, with the optimal growth temperature 20°C as the control. There were large alterations of the transcriptome profile, including significant upregulation of 11 and 12 transcripts as well as significant downregulation of 47 and 42 transcripts in the cold and heat stress groups, respectively, compared to the control. The expression of various genes encoding enzymes and transcriptional regulators, including Pfp I and Tet R family transcriptional regulators under heat stress, as well as the expression of DEAD/DEAH box helicase and the Icl R family of transcriptional regulators under cold stress, were upregulated significantly. The expression of several genes, most affiliated with Ton Bdependent receptor and siderophore receptor, was downregulated significantly under both heat and cold stress. Many of the genes associated with the metabolism of fatty acid and ABC transporters were regulated differentially under different temperature stress. The results of this survey of transcriptome and temperature stress-relevant genes contribute to our understanding of the stress-resistant mechanism in Antarctic bacteria.

关键词： Psychrobacter temperature stress transcriptome Antarctic

Microbial community structure of Arctic seawater as revealed by pyrosequencing

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2016年第6期35卷 78-84页

作者： LI Yang wang zhen lin Xuezheng The First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Bioactive Substances State Oceanic Administration

This study aimed to determine the microbial community structure of seawater in（ICE-1） and out（FUBIAO） of the pack ice zone in the Arctic *** 10 L seawater was filtrated by 0.2 μm Whatman nuclepore filters and the environmental genomic DNA was *** conducted a detailed census of microbial communities by *** of the microbial community structures indicated that these two samples had high bacterial,archaeal and eukaryotic *** and Bacteroidetes were the two dominant members of the bacterioplankton community in both samples,and their relative abundance were 51.29% and 35.39%,72.95%and 23.21%,*** was the most abundant archaeal phylum,and the relative abundance was nearly up to 100% in FUBIAO and 60% in *** for the eukaryotes,no_rank_Eukaryota,Arthropoda and no_rank_Metazoa were the most abundant groups in Sample FUBIAO,accounting for 85.29% of the total *** relative abundance of the most abundant phylum in Sample ICE-1,no_rank_Eukaryota and no_rank_Metazoa,was up to 90.69% of the total ***,Flavobacteria and Gammaproteobacteria were the top three abundant classes in the two samples at the bacterial class *** were also differences in the top ten abundant bacterial,archaeal and eukaryotic OTUs at the level of 97% similarity between the two samples.

关键词： Arctic seawater pyrosequencing microbial community