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A Middle Triassic stem-neopterygian fish from China shows remarkable secondary sexual characteristics

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Science Bulletin 2016年第4期61卷 338-344页

作者： Guang-Hui Xu li-jun zhao Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Zhejiang Museum of Natural History Hangzhou 310014 China

Secondary sexual characteristics are features that appear at sexual maturity and distinguish the two sexes of a species. They are readily observed and studied in living animals, but the phenomenon is rather more difficult to identify in fossil taxa. Here we report a new sexually dimorphic stem-neopterygian fish, Venusichthys comptus gen. et sp. nov., based on 30 exceptionally well-preserved specimens from the Middle Triassic （Pelsonian, Anisian） Luoping Lagerst^itte of eastern Yunnan, China. The discovery represents the oldest known secondary sexual characteristics in Neopterygii. These characteristics, including pointed tubercles on cranial bones, scales and fins, and hook-like contact organ anterior to the anal fin, have three inferred primary functions： maintenance of body contact between the sexes during prespawning behavior or spawning; stimulation of the females during breeding; and defense of nests and territories. Lacking a specialized anal fin in the presumed males, Venusichthys would likely have a different reproductive strategy from peltopleurids and other potentially viviparous stem-neopterygians. Moreover, Venusichthys shows a unique character combination distinguished from any other stem-neopterygian families and consequently represents a new family of this clade. Assuch, the new finding provides an important addition for understanding the behavior, reproduction, and early diversification of Neopterygii.

关键词： Sexual dimorphism Breeding tuberclesVenusichthyidae Neopterygii Actinopterygii

Applicability of anoxic-oxic process in treating petrochemical wastewater

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 133-141页

作者： li-jun zhao Fang MA Jing-bo GUO School of Chemical Engineering China University of Petroleum Beijing 102249 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

To explore the applicability of anoxic-oxic (A/O) activated sludge process for petrochemical wastewater treatment,the relationship between bacterial community structure and pollutants loading/removal efficiencies was investigated by gas chromatograph-mass spectrometry (GC-MS),polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and other conventional *** showed that when the concentrations of the influent chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) were 420～560mg/L and 64～100mg/L,respectively,the corresponding average effluent concentra-tions were 160mg/L and 55mg/L,which were 1.6 and 2.2times higher than those of the national standards in China,respectively,demonstrating the inefficient performances of A/O *** of GC-MS indicated that refractory pollutants were mainly removed by sludge adsorption,but not by ***-DGGE profile analysis suggested that the biological system was species-rich,but there was apparent succession of the bacterial community structure in different locations of the A/O *** of bacterial community structure and pollutant loadings had obvious influences on pollutants removal ***,A/O process was inapplicable for the treatment of complicated petrochemical wastewater,and strategies such as the reinforcement of pre-treatment and two-stage A/O process were suggested.

关键词： Petrochemical wastewater Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) Anoxic-oxic (A/O) process Applicability

Petrochemical wastewater treatment with a pilot-scale bioaugmented biological treatment system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1831-1838页

作者： zhao li-jun MA Fang GUO Jing-bo zhao Qing-liang School of Chemical Engineering China University of Petroleum Beijing 102249 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

In solving the deterioration of biological treatment system treating petrochemical wastewater under low temperatures, bioaugmentation technology was adopted by delivering engineering bacteria into a pilot-scale two-stage anoxic-oxic (A/O) process based on previous lab-scale study. Experimental results showed that when the concentrations of COD and NH4+-N of the influent were 370~910 mg/L and 10~70 mg/L, the corresponding average concentrations of those of effluent were about 80 mg/L and 8 mg/L respectively, which was better than the Level I criteria of the Integrated Wastewater Discharge Standard (GB8978-1996). According to GC-MS analysis of the effluents from both the wastewater treatment plant (WWTP) and the pilot system, there were 68 kinds of persistent organic pollutants in the WWTP effluent, while there were only 32 in that of the pilot system. In addition, the amount of the organics in the effluent of the pilot system reduced by almost 50% compared to that of the WWTP. As a whole, after bioaugmentation, the organic removal efficiency of the wastewater treatment system obviously in- creased.

关键词： Bioaugmentation Petrochemical wastewater Pilot-scale study GC/MS

One-way quantum deficit and quantum coherence in the anisotropic X Y chain

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Science China(Physics,Mechanics & Astronomy) 2017年第3期60卷 42-47页

作者： Biao-liang Ye Bo li li-jun zhao Hai-jun Zhang Shao-Ming Fei School of Physics and Electronic Information Shangrao Normal University Shangrao 334001 China School of Mathematics & Computer Science Shangrao Normal University Shangrao 334001 China School of Mathematical Sciences Capital Normal University Beijing 100048 China Max-Planck-lnstitute for Mathematics in the Sciences Leipzig 04103 Germany

In this study, we investigate pairwise non-classical correlations measured using a one-way quantum deficit as well as quantum coherence in the XY spin-1/2 chain in a transverse magnetic field for both zero and finite temperatures. The analytical and numerical results of our investigations are presented. In the case when the temperature is zero, it is shown that the one-way quantum deficit can characterize quantum phase transitions as well as quantum coherence. We find that these measures have a clear critical point at λ = 1. When λ 1, the one-way quantum deficit has an analytical expression that coincides with the relative entropy of coherence. We also study an XX model and an Ising chain at the finite temperatures.

关键词： one-way quantum deficit quantum coherence quantum phase transitions XY chain

A Discriminative Algorithm for Indoor Place Recognition Based on Clustering of Features and Images

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International Journal of Automation and computing 2017年第4期14卷 407-419页

作者： Ke Wang Xue-Xiong Long Rui-Feng li li-jun zhao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 China

In order to solve the problem of indoor place recognition for indoor service robot, a novel algorithm, clustering of features and images （CFI）, is proposed in this work. Different from traditional indoor place recognition methods which are based on kernels or bag of features, with large margin classifier, CFI proposed in this work is based on feature matching, image similarity and clustering of features and images. It establishes independent local feature clusters by feature cloud registration to represent each room, and defines image distance to describe the similarity between images or feature clusters, which determines the label of query images. Besides, it improves recognition speed by image scaling, with state inertia and hidden Markov model constraining the transition of the state to kill unreasonable wrong recognitions and achieves remarkable precision and speed. A series of experiments are conducted to test the algorithm based on standard databases, and it achieves recognition rate up to 97% and speed is over 30 fps, which is much superior to traditional methods. Its impressive precision and speed demonstrate the great discriminative power in the face of complicated environment.

关键词： Indoor place recognition locally and globally independent clustering of features and images (CFI) state inertia hidden Markov model.

Deliquescence and Efflorescence Processes of Aerosol Particles Studied by in situ FTIR and Raman Spectroscopy

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Chinese Journal of Chemical Physics 2008年第1期21卷 1-11页

作者： li-jun zhao Feng Wang Kun Zhang Qing-xuan Zeng Yun-hong Zhang The Institute of Chemical Physics School of Science Beijing Institute of Technology Beijing 100081China School of Aerospace Science and Engineering Beiy'ing Institute of Technology Beijing 100081 China

Deliquescence and efflorescence are the two most important physicochemical processes of aerosol particles. In deliquescence and efflorescence cycles of aerosol particles, many fundamental problems need to be investigated in detail on the molecular level, including ion and molecule interactions in supersaturated aerosols, metastable solid phases that may be formed, and microscopic structures and deliquescence mechanisms of aerosol particles. This paper presents a summary of the progress made in recent investigations of deliquescence and efflorescence processes of aerosol particles by four common spectral techniques, which are known as Raman/electrodynamic balance, Fourier transform infrared/aerosol flow tube, Fourier transform infrared/attenuated total reftection, and confocal Raman on a quartz substrate.

关键词： Aerosol Deliquescence Efflorescence Raman/electrodynamic balance Fourier transform infrared/aerosol flow tube Fourier transform infrared/attenuated total reflection Confocal Raman

Quantum nonlocality can be distributed via separable states

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维普期刊数据库

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Science China(Physics,Mechanics & Astronomy) 2018年第7期61卷 79-82页

作者： li-jun zhao Yu-Min Guo XianQing li-Jost Shao-Ming Fei School of Mathematical Sciences Capital Normal University Beijing 100048 China Max-Planck-Institute for Mathematics in the Sciences Leipzig 04103 Germany School of Mathematics and Statistics Hainan Normal University Haikou 571158 China

Quantum nonlocality is one of the most astonishing features in quantum *** is of great importance in understanding the conceptual foundations of quantum theory and is closely related to certain quantum information processing such as quantum protocols for decreasing communication complexity[1]and secure quantum communication[2,3],see refs.[4-9]for more details.

关键词：散布状态分离信息处理复杂性量子论通讯协议

Effects of probiotic therapy on hepatic encephalopathy in patients with liver cirrhosis:an updated meta-analysis of six randomized controlled trials

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 354-360页

作者： jun Xu Rui Ma li-Feng Chen li-jun zhao Kan Chen Ren-Bing Zhang Department of Surgery Zhejiang University Hospital Zhejiang University

BACKGROUND： liver cirrhotic patients with hepatic encephalopathy have poor prognosis. Probiotics alter the intestinal microbiota and reduce the production of ammonia. We conducted a meta-analysis about the role of probiotics on liver cirrhotic patients with hepatic *** SOURCES： We collected the relevant literatures up to February 21, 2014 from databases of PubMed, EMBASE and the Cochrane Central Register of Controlled Trials. A statistical analysis was conducted by RevMan 5.2 and STATA 12.0 ***： Six randomized controlled trials involving 496 liver cirrhotic patients were included. The results showed that probiotic therapy significantly reduced the development of overt hepatic encephalopathy（OR [95% CI]： 0.42 [0.26, 0.70],P=0.0007）. However, probiotics did not affect mortality, levels of serum ammonia and constipation（mortality： OR [95% CI]：0.73 [0.38, 1.41], P=0.35; serum ammonia： WMD [95% CI]：-3.67 [-15.71, 8.37], P=0.55; constipation： OR [95% CI]： 0.67 [0.29,1.56], P=0.35）.CONCLUSION： Probiotics decrease overt hepatic encephalopathy in patients with liver cirrhosis.

关键词： probiotics hepatic encephalopathy liver cirrhosis ammonia meta-analysis

The effects of calcium combined with chitosan amendment on the bioavailability of exogenous Pb in calcareous soil

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Journal of Integrative Agriculture 2020年第5期19卷 1375-1386页

作者： CHANG Hui-qing WANG Qi-zhen li zhao-jun WU Jie XU Xiao-feng SHI zhao-yong Henan University of Science and Technology Luoyang 471000P.R.China Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/China-New Zealand Joint Laboratory for Soil Molecular EcologyInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China

Lead(Pb) in soil may accumulate in crops and enter the human body. This study aimed to understand the speciation transformation and accumulation characteristics of exogenous Pb in calcareous soil with or without the application of soil amendments. Field experiments with continuous maize cultivation have been carried out for two years. The results showed that the contents of total Pb were slightly lower in 2016 than in 2015 for the same treatments;however, no significant difference between the years was observed. Soil Pb existed mainly in the residual fraction without exogenous Pb addition, and its proportion was more than 33% of the total soil Pb in the control and Ca treatments. When Pb was added to calcareous soil, Pb existed largely in the oxidizable and reducible fractions during the two-year experimental period, and those fractions made up over 83% of the total Pb. The proportion of the water-soluble Pb, regardless of the addition of Pb, was the lowest and was less than 0.0019% in all treatments, but the addition of Ca and chitosan amendments reduced the water-soluble and exchangeable Pb contents. The Pb content in different parts of maize followed the order root>leaf>stem>grain during the experimental period. Although maize had low transfer and enrichment factors in calcareous soil, which make the Pb content in the grain show no significant difference among the five treatments in the same year, adding Ca and chitosan to calcareous soil can reduce the Pb contents of maize, especially reduce the Pb contents of root, stem and leaf. Therefore, the addition of calcium and chitosan is an effective strategy for reducing Pb availability in calcareous soils.

关键词： exogenous Pb maize calcareous soil speciation transformation amendments