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Effects of plant density and nitrogen rate on cotton yield and nitrogen use in cotton stubble retaining fields

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Journal of Integrative Agriculture 2021年第8期20卷 2090-2099页

作者： wang shi-hong MAO Li-li shi Jia-liang NIE Jun-jun SONG Xian-liang SUN Xue-zhen Agronomy College Shandong Agricultural UniversityTai’an 271018P.R.China Liaocheng Academy of Agricultural Sciences Liaocheng 252000P.R.China Dezhou Academy of Agricultural Sciences Dezhou 253000P.R.China

Increasing nitrogen(N)rate could accelerate the decomposition of crop residues,and then improve crop yield by increasing N availability of soil and N uptake of ***,it is not clear whether N rate and plant density should be modified after a long period of cotton stubble return with high N *** study seeks to assess the effects of N rate and plant density on cotton yield,N use efficiency,leaf senescence,soil inorganic N,and apparent N balance in cotton stubble return fields in Liaocheng,China,in 2016 and *** plant densities 5.25(D_(5.25)),6.75(D_(6.75))and 8.25(D_(8.25))plants m^(-2) and five N rates 0(N_(0)),105(N_(105)),210(N_(210)),315(N315),and 420(N420)kg ha^(-1) were *** to the combination used by local farmers(D_(5.25)N_(315)),a 33.3%N reduction and a 28.6%increase in plant density(D_(6.75)N_(210))can maintain high cotton yield,while a 66.7%N reduction at 6.75 plants m^(-2)(D_(6.75)N_(105))can only achieve high yield in the first *** yield increased with the increase of N rate and plant density,and the highest yield was obtained under 420 kg N ha^(-1) at 8.25 plants m^(-2)(D_(8.25)N_(420))across the two years under *** to D5.25N315,N agronomic efficiency(NAE)and N recovery efficiency(NRE)in D_(6.75)N_(210) increased by 30.2 and 54.1%,respectively,and NAE and NRE in D6.75N105 increased by 104.8 and 88.1%,*** inorganic N decreased sharply under 105 kg N ha^(-1),but no change was found under 210 kg N ha^(-1) at 6.75 plants m^(-2).N deficit occurred under 105 kg N ha^(-1),but it did not occurr under 210 kg N ha^(-1) at 6.75 plants m^(-2).Net photosynthetic rate and N concentration of leaves under N rate ranging from 210 to 420 kg ha^(-1) were higher than those under N rate of 0 or 105 kg N ha^(-1) at all three *** findings suggest that D6.75N210 is a superior combination in cotton stubble retaining fields in the Yellow River Valley and other areas with similar ecologies.

关键词： leaf senescence N application rate N use efficiency seed cotton yield soil apparent N surplus

论大司农在武帝朝拓边政策中的执掌变动及作用

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中国农史 2018年第3期37卷 48-59页

作者：王世红安庆师范大学人文学院安徽安庆246051

武帝实施"外攘夷狄"的拓边政策,随着拓边深入和疆域拓展,国家出现了一系列严重的财政问题。为了推进拓边政策和解决财政问题,汉代大司农的执掌出现了替代少府而辖盐铁、搜粟都尉"大农化"以及所辖人口增多与土地增广等变动,大司农官在武... 详细信息

武帝实施"外攘夷狄"的拓边政策,随着拓边深入和疆域拓展,国家出现了一系列严重的财政问题。为了推进拓边政策和解决财政问题,汉代大司农的执掌出现了替代少府而辖盐铁、搜粟都尉"大农化"以及所辖人口增多与土地增广等变动,大司农官在武帝朝实施拓边政策中也发挥了重要作用。

关键词：汉武帝边疆拓边大司农

Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU Wei JIAO Jinxu LUO Dusha ZHOU Junjie shi Lifen wang Weiwei LI Changqing wang Peng XIONG Dehua LI hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR

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Computers, Materials & Continua 2025年第1期82卷 1109-1128页

作者： Hailong wang Junchao shi School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China

A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number *** the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection *** terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background *** addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production *** experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line *** Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition.

关键词： Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun Fu hong-Wei Li Jian-hong shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Unilateral sacrospinous ligament fixation for treatment of genital prolapse

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Chinese Medical Journal 2010年第15期123卷 1995-1998页

作者： PENG Ping ZHU Lan LANG Jing-he wang Wen-yan shi hong-hui Department of Obstetrics and Gynecology Peking Union College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

Background Genital prolapse affects 30% of middle-aged and older women and is becoming a major public health concern. Sacrospinous ligament fixation is an effective and safe procedure for vaginal vault prolaps with a low recurrence and complication rate. This study aimed to investigate the efficacy and safety of unilateral sacrospinous ligament fixation （SSLF） for the management of pelvic organ prolapse （POP）.Methods Forty patients with severe prolapse of pelvic organ undergoing unilateral SSLF were retrospectively *** this study, all patients were staged by the value of POP-Q. All procedures were performed by a senior physician. The characteristics of these patients and their immediate and short-term post-operative outcome were recorded. All patients were seen six weeks and six months after the surgery. The evaluation included standardized questionnaire and site-specific vaginal examination by one *** The average operation time was 65-92 minutes. The average blood loss was 83-188 ml. The average hospitalization time was 6.1 days. The average cost was 5885 yuan. The average day of urethral catheter removal after the operation was 2.1 days. The incidence of postoperative morbidity was 17.1%. One （2.4%） patient had hematoma in the right pelvic. The mean length of postoperative follow-up for 35 patients was 13.1 months. The rate of follow-up was 87.5%. One （2.9%） patient showed recurrent vaginal vault prolapse six months after the surgery. The objective success rate of pelvic organ prolapse was 85% （34/40）. There was significant difference between the POP-Q of Aa, Ba, Ap, Bp,and D before and after operation （P 〈0.001 ）. Five （14.3%） patients complained lower back pain, gluteal pain or right groin pain. Three （8.6%） patients developed de novo stress incontinence. Vaginal disabsorbable sutures were found in three （8.6%） patients. One （2.9%） patient had de novo urge *** Unilateral SSLF was both cost and treatment effective managem

关键词： unilateral sacrospinous ligament fixation genital prolapse complication

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili wang Jiancheng Huang Yanan Du Wei Huang Yufeng Xue Xiaokun Xu Guannan Zhong Yuanyuan shi Bin hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

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土钉支护结构极限支护深度的研究

岩土力学 2009年第7期30卷 2087-2090页

作者：屠毓敏王士宏浙江大学土木工程系杭州310027 水利部淮河水利委员会建设局安徽蚌埠233001

土钉墙支护软弱地基基坑,只能适用于一定的开挖深度,即土钉基坑支护结构具有极限开挖深度。为此,提出了土钉支护结构极限开挖深度的确定方法,以淤泥类地层基坑作为研究对象,研究了土钉支护结构的极限开挖深度问题,以及研究了土钉墙墙面... 详细信息

土钉墙支护软弱地基基坑,只能适用于一定的开挖深度,即土钉基坑支护结构具有极限开挖深度。为此,提出了土钉支护结构极限开挖深度的确定方法,以淤泥类地层基坑作为研究对象,研究了土钉支护结构的极限开挖深度问题,以及研究了土钉墙墙面坡度、地面超载、土层物理力学性指标以及土钉直径等变化时对极限开挖深度的影响。对于位于淤泥类、淤泥质类土层中的基坑,其极限开挖深度可分别取为5.0m和6.0m。

关键词：土钉墙基坑极限开挖深度软弱地基

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造纸企业集团化发展进程与思考

中华纸业 2009年第19期30卷 72-75页

作者：王世宏山东晨鸣纸业集团股份有限公司

我国经济结构长期存在生产经营规模小、专业化程度低、区域产业结构雷同、盲目过度竞争等弊端,同样,造纸行业也面临着这样的问题,在一定程度上制约了民族造纸业的健康发展。近年来,随着全球经济一体化的不断深入,中国纸业发展的内外环... 详细信息

我国经济结构长期存在生产经营规模小、专业化程度低、区域产业结构雷同、盲目过度竞争等弊端,同样,造纸行业也面临着这样的问题,在一定程度上制约了民族造纸业的健康发展。近年来,随着全球经济一体化的不断深入,中国纸业发展的内外环境发生了巨大变化,

关键词：晨鸣集团集团化战略布局发展经验