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城市化进程影响下的古镇传统街巷空间特征解析及其优化路径研究——以上海新场古镇为例

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华中建筑 2025年第1期43卷 180-184页

作者：彭泓宇朱江华中科技大学建筑与城市规划学院郑州市郑东高新产业发展有限公司

为探究上海新场古镇在城市化进程中的传统街巷空间特征,该文采用空间句法分析,通过构建轴线分析模型并进行可理解度、整合度和深度的特征分析,对古镇的空间格局和公共节点配置两个维度进行了定量研究。研究表明,尽管城市化带来了空间形... 详细信息

为探究上海新场古镇在城市化进程中的传统街巷空间特征,该文采用空间句法分析,通过构建轴线分析模型并进行可理解度、整合度和深度的特征分析,对古镇的空间格局和公共节点配置两个维度进行了定量研究。研究表明,尽管城市化带来了空间形态的现代化变化,但古镇的整体空间特征和历史文化价值未能得到充分保护,传统街巷的空间活力受到一定影响。基于该研究结果,在古镇保护与发展的过程中,仍需深入挖掘传统街巷的历史文化内涵,并探索更加有效的保护与更新路径,以实现历史文化与现代化发展的平衡。

关键词：城市化进程传统街巷空间特征空间句法新场古镇

Yield potential and nitrogen use efficiency of China's super rice

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Journal of Integrative Agriculture 2017年第5期16卷 1000-1008页

作者： WANG fei peng Shao-bing National Key Laboratory of Crop Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River Ministry of Agriculture/College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

In 1996, a mega project that aimed to develop rice varieties with super-high yield potential （super rice） was launched by the Ministry of Agriculture （MOA） in China using a combination of the ideotype approach and intersubspecific heterosis. Significant progress has been made in the last two decades, with a large number of super rice varieties being approved by the MOA and the national average grain yield being increased from 6.21 t ha^-1 in 1996 to 6.89 t ha^-1 in 2015. The increase in yield potential of super rice was mainly due to the larger sink size which resulted from larger panicles. Moreover, higher photosynthetic capacity and improved root physiological traits before heading contributed to the increase in sink size. However, the poor grain filling of the later-flowering inferior spikelets and the quickly decreased root activity of super rice during grain filling period restrict the achievement of high yield potential of super rice. Furthermore, it is widely accepted that the high yield potential of super rice requires a large amount of N fertilizer input, which has resulted in an increase in N consumption and a decrease in nitrogen use efficiency （NUE）, although it remains unclear whether super rice per se is responsible for the latter. In the present paper, we review the history and success of China＇s Super Rice Breeding Pro- gram, summarize the advances in agronomic and physiological mechanisms underlying the high yield potential of super rice, and examine NUE differences between super rice and ordinary rice varieties. We also provide a brief introduction to the Green Super Rice Project, which aims to diversify breeding targets beyond yield improvement alone to address global concerns around resource use and environmental change. It is hoped that this review will facilitate further improvement of rice production into the future.

关键词： super rice yield potential nitrogen use efficiency Green Super Rice

Performance of FAST with an Ultra-Wide Bandwidth Receiver at 500–3300 MHz

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Research in Astronomy and Astrophysics 2023年第7期23卷 197-205页

作者： Chuan-peng Zhang peng jiang Ming Zhu Jun Pan Cheng Cheng Hong-fei Liu Yan Zhu Chun Sun FAST Collaboration National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China College of Earth Sciences Guilin University of TechnologyGuilin 541004China

The Five-hundred-meter Aperture Spherical radio Telescope(FAST)has been running for several years.A new ultra-wide bandwidth(UWB)receiver,simultaneously covering 500-3300 MHz,has been mounted in the FAST feed cabin and has passed a series of observational *** whole UWB band is separated into four independent *** band has 1,048,576 channels in total,resulting in a spectral resolution of 1 *** 500-3300 MHz,the antenna gain is around 14.3-7.7 K Jy^(-1),the aperture efficiency is around 0.56-0.30,the system temperature is around 88-130 K,and the half-power beamwidth is around 7.6'-1.6'.The measured standard deviation of pointing accuracy is better than~7.9"when zenith angle is within 26.4°.The sensitivity and stability of the UWB receiver are confirmed to satisfy expectations through spectral observations,e.g.,HI and *** FAST UWB receiver has already demonstrated good performance in capturing sensitive observations for various scientific goals.

关键词： instrumentation:detectors telescopes line:profiles

SNP Analysis and Haplotype Identification in Chymotrypsin Inhibitor-2 (CI-2) Gene of Barley

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Agricultural Sciences in China 2009年第1期8卷 8-14页

作者： ZENG Xiang-hui WEI Yu-ming jiang Qian-tao QI peng-fei ZHENG You-liang Triticeae Research Institute Sichuan Agricultural University Ya＇an 625014 P.R.China Key Laboratory of Crop Genetic Resources and Improvement in Southwest China Ministry of Education/Sichuan Agricultural University Ya＇an 625014 P.R.China

Barley chymotrypsin inhibitor-2 （CI-2） was considered to be a promising candidate for enhancing the nutritional value of other cereals by increasing its concentration as it is rich in lysine than any other storage protein. Also, it was proposed that CI-2 might play an important role in the inhibition of proteolytic enzymes from pests or pathogens as CI-2 can strongly inhibit chymotrypsin and subtilisin. In this study, a total of 93 CI-2 gene sequences were isolated from wild and cultivated barley. 48 SNPs and 4 indels were detected across the entire sequences. The frequency of SNPs in the noncoding region （1 out of 9 bases） was slightly higher than that in the coding region （1 out of 10.7 bases）. In all, 33.3% of the candidate cSNPs resulted in amino acid changes. As a total, the 24 cSNPs resulted in 15 amino acid changes. Ten distinguishable haplotypes were detected, among which 3 haplotypes were shared in the most barley accessions, whereas the rest of the haplotypes appeared at a lower frequency. In addition, three haplotypes （haplotype 4, 8, and 9） were unique for single accessions. These results suggested that low diversity at the CI-2 locus was detected among the cultivated and wild barley.

关键词： barley chymotrypsin inhibitor SNP haplotype

Single-photon source with sub-MHz linewidth for cesium-based quantum information processing

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Frontiers of physics 2023年第6期18卷 275-281页

作者： Hai He peng-fei Yang peng-fei Zhang Gang Li Tian-Cai Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Collaborative Innovation Center of Extreme OpticsInstitute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China

A single-photon source with narrow bandwidth,high purity,and large brightness can efficiently interact with material qubits strongly coupled to an optical microcavity for quantum information ***,we experimentally demonstrate a degenerate doubly resonant single-photon source at 852 nm by the cavity-enhanced spontaneous parametric downconversion process with a 100%duty cycle of *** single photon source possesses both high purity with a second-order correlation g^((2))_(h)(0)=0.021 and narrow linewidth with△_(V_(sp))=(800±13)*** single-photon s Single-photon source with sub-MHz linewidth for cesium-based quantum information processingource is compatible with the cesium atom D2 line and can be used for cesium-based quantum information processing Single-photon source with sub-MHz linewidth for cesium-based quantum information processing0.021.

关键词： single-photon source sub-MHz linewidth few longitudinal modes quantum information processing

Analyzing Left-truncated and Right-censored Data under Cox Models with Long-term Survivors

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 241-252页

作者： fei-peng ZHANG YONG ZHOU School of Statistics and Management Shanghai University of Finance and Economics Academy of Mathematics and Systems Science Chinese Academy of Sciences

We analyze left-truncated and right-censored data using Cox proportional hazard models with long-term survivors. The estimators of covariate coefficients and the long-term survivor proportion are obtained by the partial likelihood method, and their asymptotic properties are also established. Simulation studies demonstrate the performance of the proposed estimators, and an application to a real dataset is provided.

关键词： semiparametric proportional hazards models left-truncated and right-censored data long-termsurvivors

Extant primates and development of primatology in China: Publications, student training, and funding

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Zoological Research 2018年第4期39卷 249-254页

作者： peng-fei Fan Chi Ma School of Life Sciences Sun Yat-Sen University

China supports the richest non-human primate diversity in the northern hemisphere, providing an excellent opportunity for Chinese primatologists to take a leading role in advancing the study of primatology Primatology in China began to flourish after 1979. To date, Chinese primatologists have published more than 1 000 papers in journals indexed by the Chinese Science Citation Database and the Web of Science Core Collection, and universities and academic institutions have trained 107 PhD students and 370 Masters students between 1984 and 2016. In total, the National Science Foundation of China has funded 129 primate projects （RMB 71.7 million） supporting 59 researchers from 28 organizations. However, previous research has also shown obvious species bias. Rhinopithecus roxellana, Rhinopithecus bieti, and Macaca mulatta have received much greater research attention than other species. Researchers have also tended to continue to study the same species （55.2%） they studied during their PhD training. To promote the development of primatology in China, we suggest （1） the need for a comprehensive primatology textbook written in Chinese, （2） continued training of more PhD students, and （3） encouragement to study less well-known primate species.

关键词： Gibbon Snub-nosed monkey Leafmonkey Macaque Slow Iories

Studies on Electrochemical Property of LiFePO_4/C as Cathode Material for Lithium Ion Batteries

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Chemical Research in Chinese Universities 2006年第1期22卷 73-75页

作者： HUANG Xiao-wen SHI peng-fei Faculty of Applied Chemistry Harbin Institute of Technology Harbin 150001 P.R. China College of Material Science and Engineering Shandong University of Science and Technology Qingdao 266510 P. R. China

LiFePO4/C samples were prepared at different temperatures by adding sngar to the synthetic precursor. The samples were characterized by X-ray diffraction（XRD）. Their crystal phases show an olivine structure. Only the sample obtained at 700℃ has a larger discharge capacity, which has good electrochemical properties： its discharge specific capacity is 120. 3 mAh/g at a current of 0. 05 mA, and its capacity fade is very low after 20 cycles. It is demonstrated that the best synthetic temperature should be 700℃.

关键词： Olivine Lithium ion battery Carbon-coated LiFePO4

Rural transformation,income growth,and poverty reduction by region in China in the past four decades

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Journal of Integrative Agriculture 2023年第12期22卷 3582-3595页

作者： SHI peng-fei HUANG Ji-kun China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871P.R.China Research Center for Rural Economy Ministry of Agriculture and Rural AffairsBeijing 100810P.R.China

China has experienced rapid rural transformation in the past four *** the rapid transformation is a significant rise in rural household income and a substantial fall in rural *** paper examines the evolutions of and the relationships between rural transformation(high-value agriculture and rural non-farm employment)and its outcomes(per capita rural income and rural poverty incidence)using provincial-level *** results show that 31 provinces/autonomous regions/municipalities have undergone significant rural transformation,but the level and speed of rural transformation differed ***,an increased level of rural transformation is often associated with higher per capita rural income and reduced rural poverty ***,a category of provincial rural transformation based on high-value agriculture and rural non-farm employment is also *** further discuss the likely impacts of institutions,policies,and investments(IPIs)on rural transformation and conclude with policy implications.

关键词： rural transformation high-value agriculture non-farm employment income poverty China