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1978年以来国有企业改革史述论

湖南工业大学学报（社会科学版） 2024年第5期29卷 1-9,54页

作者：武力张克利中国社会科学院当代中国研究所北京100009

国有企业是中国特色社会主义的重要物质基础和政治基础,在中国的经济体制改革中始终具有突出的政治经济地位。从1978年中共十一届三中全会国有企业放权让利改革开始,国有企业改革的步伐从未停止,循序渐进、不断深化。每个时期的国有企... 详细信息

国有企业是中国特色社会主义的重要物质基础和政治基础,在中国的经济体制改革中始终具有突出的政治经济地位。从1978年中共十一届三中全会国有企业放权让利改革开始,国有企业改革的步伐从未停止,循序渐进、不断深化。每个时期的国有企业改革都受这个时期的发展要求和改革条件制约,都需要智慧和勇气。作为经济体制改革的主要内容,国有企业改革难度最大,首当其冲,而且决定了中国发展的方向,直接关系到改革、发展、稳定三者的平衡。中共十八大以来,面对社会主义矛盾变化和经济发展由高速度转向高质量的新形势新任务,国有企业通过全面深化改革,在党建引领、战略安全、监督考核和积极灵活、主动创新、科技领跑等方面发生了根本性变化,不断做强做优做大,增强了核心功能,提升了核心竞争力,彰显出国有企业在中国式现代化建设中的主导地位,体现出社会主义体制的优越性。46年的国有企业改革,其历程虽然艰难,但取得了显著成功,其从理论和实践上都证明了公有制是可以与市场经济有机结合的,也极大丰富和发展了马克思主义政治经济学和社会主义理论。

关键词：国有企业改革史制度变迁市场经济

Effect of combining biogeotextile and vegetation cover on the protection of steep slope of highway in northern China: A runoff plot experiment

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International Journal of Sediment Research 2023年第3期38卷 387-395页

作者： Hongyuan Liu Liang Liu keli zhang Ren Geng Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Co-Innovation Center for Sustainable Forestry in Southern China of Jiangsu Province Key Laboratory of Soil and Water Conservation and Ecological Restoration of Jiangsu Province Nanjing Forestry University School of Geography Faculty of Geographical Science Beijing Normal University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute

Biogeotextiles can be used to facilitate the formation of vegetation cover and to reduce soil *** have demonstrated that only biogeotextile or vegetation cover can greatly reduce soil ***, information about the effects of the combination of biogeotextile and vegetation cover on soil erosion is still limited, despite that the combination is the commonly practical form for bare road slope protection. Experimental plots, consisting of a relatively loose surface layer and a compacted sublayer,were constructed using movable soil-bin trolleys(200 × 100 × 40 cm3) filled with silt loam sieved through 1-cm screen. The plots were seeded with a seed mixture of tall fescue(Festuca elata Keng ex ***) and alfalfa(Medicago sativa L.) as a grass-legume regime. Then the plots were covered with three types of biogeotextile, i.e., coir blanket(CB), mixed coir-straw blanket(MB), and straw blanket(SB).A bare slope(BS) was constructed as the control experiment. Irrigation was applied to ensure vegetation germination and growth. Plant characteristics were measured after every 20 days. Laboratory simulated rainfall of 71 mm/h intensity was applied to each plot for 60 min after 20, 40, and 60 days. Surface runoff and sediment were collected every 5 min during rainfall. The results showed that the MB and SB promoted increased total emergence density of plants by 47% and 23%, respectively, compared to case of vegetation growth without biogeotextiles. The dense structure of the CB impeded the emergence of alfalfa, leading to 9% lower total emergence density. Compared with bare slope(0 day BS), biogeotextiles increased runoff by 3%(MB)-19%(CB) and reduced erosion by 96%(MB and SB)-98%(CB). After 60 days,vegetation cover reduced runoff by 54% and reduced erosion by 81% compared with the BS case. The combination of biogeotextile and vegetation cover reduced runoff by 44%(CB)-62%(SB) and reduced erosion by no less than 99% compared to the BS case. Compared with biogeo

关键词： Biogeotextile Vegetation cover Slope protection Runoff control Erosion control

基于GB-SAR的矿山边坡局部变形演化与失稳预测

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中国安全生产科学技术 2024年第4期20卷 85-93页

作者：张克利马海涛张建全姚爱敏闫宇蕾尹利洁北京城建勘测设计研究院有限责任公司北京100101 中国安全生产科学研究院北京100012

为了提高地基合成孔径雷达(ground-based synthetic aperture radar, GB-SAR)边坡监测效果与失稳预测能力,在广东省某石灰石矿山架设地基雷达,开展实地监测试验,结合矿山地质条件与监测数据研究不同类型的岩体变形演化特征,根据变形特... 详细信息

为了提高地基合成孔径雷达(ground-based synthetic aperture radar, GB-SAR)边坡监测效果与失稳预测能力,在广东省某石灰石矿山架设地基雷达,开展实地监测试验,结合矿山地质条件与监测数据研究不同类型的岩体变形演化特征,根据变形特征选择位移最大点的监测数据利用速度倒数法进行失稳预测。通过分析典型案例的监测数据来优化速度倒数法的算法,进而对矿山试验数据进行研究。研究结果表明:通过分析雷达三维模型变形图的局部位移差异,能够初步判断边坡岩体的变形破坏方式;适当增大移动平均滤波法的移动时间周期C,能够更早地发现灾害征兆,更好地识别岩体加速变形阶段及临滑阶段。研究结果可为基于雷达的滑坡预测提供参考。

关键词：边坡工程变形监测 GB-SAR 失稳预测

非酒精性脂肪性肝炎患者血清前神经降压素和微小RNA-122水平变化及其诊断脂肪性肝炎的价值探讨

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实用肝脏病杂志 2024年第2期27卷 202-205页

作者：童静张珂瓈李昌平四川省泸州市纳溪区人民医院消化肾病科 646300 西南医科大学附属医院消化内科

目的探讨非酒精性脂肪性肝病(NAFLD)患者血清脂肪细胞因子前神经降压素(Pro-NT)和微小RNA-122(miRNA-122)水平变化及其诊断非酒精性脂肪性肝炎(NASH)的潜在价值。方法2017年1月~2022年6月我院诊治的NAFLD患者159例和同期入院体检的健康... 详细信息

目的探讨非酒精性脂肪性肝病(NAFLD)患者血清脂肪细胞因子前神经降压素(Pro-NT)和微小RNA-122(miRNA-122)水平变化及其诊断非酒精性脂肪性肝炎(NASH)的潜在价值。方法2017年1月~2022年6月我院诊治的NAFLD患者159例和同期入院体检的健康人90例,行腹部超声检查,采用ELISA法检测血清Pro-NT水平,采用RT-PCR法检测血清miRNA-122。对NAFLD患者行肝活检检查,确定NASH诊断。应用受试者工作特征曲线(ROC)并计算曲线下面积(AUC)评估指标诊断的敏感度和特异度。结果在159例NAFLD患者中,经肝活检检查诊断NASH患者49例和单纯性脂肪肝110例;NASH患者BMI为(28.4±1.2)kg/m^(2),显著大于NAFLD患者【(27.3±1.4)kg/m^(2),P<0.05】;NASH患者血清ALT、AST、空腹血糖(FBG)、胰岛素、HOMA-IR和尿酸水平分别为62(48,96)U/L、56(47,85)U/L、(5.9±0.6)mmol/L、10.2(8.8,13.4)μU/mL、2.6(1.8,3.4)和496(392,515)μmol/L,均显著高于NAFLD患者38(25,53)U/L、32(21,49)U/L、(5.3±0.6)mmol/L、9.0(7.2,12.6)μU/mL、2.2(1.3,2.7)和446(351,495)μmol/L,P<0.05;血清Pro-NT和miRNA-122分别为167(148.4,186.9)pmol/L和8.2(2.0,29.3),显著高于NAFLD患者【分别为82(53.0,100.4)pmol/L和2.2(1.4,10.6),P<0.05】;NAFLD患者上述指标又显著高于健康人(P<0.05);分别以血清Pro-NT≥112 pmol/L和miRNA-122≥7.08为截断点,结果Pro-NT诊断NASH的AUC为0.824,灵敏度、特异度、阳性预测值和阴性预测值分别为80.0%、80.0%、84.9%和82.3%,经Delong法检验,显著优于miRNA-122诊断(分别为0.637、56.0%、70.0%、76.5%和56.8%,P<0.05)。结论应用血清Pro-NT水平在NAFLD患者中初筛NASH可能有一定的临床价值,值得进一步研究。

关键词：非酒精性脂肪性肝炎前神经降压素微小RNA-122 诊断

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东北黑土区冻融循环对切沟沟壁崩塌的影响

水土保持学报 2024年第2期38卷 109-117,325页

作者：贾晨阳刘宏远于悦马芊红柯奇画张科利北京师范大学地理科学学部地表过程与资源生态国家重点实验室北京100875

[目的]通过测量冻融循环期间沟壁崩塌体积来评价冻融循环对切沟侵蚀的贡献。[方法]2016-2018年间,选取36条切沟共计463个崩塌点开展了野外调查。基于调查结果,切沟沟壁崩塌主要表现为2种类型:块状崩塌和松散堆积。在每个崩塌点测量2种... 详细信息

[目的]通过测量冻融循环期间沟壁崩塌体积来评价冻融循环对切沟侵蚀的贡献。[方法]2016-2018年间,选取36条切沟共计463个崩塌点开展了野外调查。基于调查结果,切沟沟壁崩塌主要表现为2种类型:块状崩塌和松散堆积。在每个崩塌点测量2种堆积体的形态参数:崩塌土壤的体积、切沟横断面的宽度和深度,以及相应沟壁土壤的剪切力和硬度。[结果](1)3年研究期间冻融作用导致的沟壁崩塌强度平均为16.12 m^(3)/(km·a)。2种崩塌类型在切沟内随机发生,单点冻融崩塌量主要集中在0~3 m ^(3),但块状崩塌导致的土方量更大。(2)切沟横断面宽度和深度是沟壁崩塌的主要影响因素,崩塌量随宽深比增大而增加,当宽深比>2.71后,崩塌量迅速增加。(3)切沟崩塌量与沟壁土壤的剪切力和硬度等紧密相关。[结论]沟壁冻融崩塌与切沟宽度和深度紧密相关,冻融崩塌量占切沟侵蚀泥沙产量的3.28%~23.68%,其影响与沟头溯源侵蚀相当。研究结果为定量评价冻融循环对切沟侵蚀贡献提供数据支撑。

关键词：切沟沟壁崩塌冻融循环黑土切沟侵蚀

Effects of soil rock fragment content on the USLE-K factor estimating and its influencing factors

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International Soil and Water Conservation Research 2023年第2期11卷 263-275页

作者： Miaomiao Yang Qinke Yang keli zhang Chunmei Wang Guowei Pang Yuru Li College of Urban and Environmental Sciences Northwest UniversityXi'an710127China College of Geography Beijing Nomal UniversityBeijing100875China The First Institute of Geoinformation Mapping Ministry of Natural Resources of the People's Republic of ChinaXian710054China

Rock fragments are an important component of soil,and their presence has a significant impact on soil erosion and sediment *** this paper,the effects of rock fragments in the topsoil profile(RFP)and rock fragments on the soil surface(RFS)on the soil erodibility factor(K)were assessed at a global *** spatial pattern of the relationship between stoniness and erodibility(RS-K)and its predominant factors were explored through correlation analysis,pattern analysis,and random forest model *** results were as followings:(1)The existence of RFP increased K by 2.84%.The RFS of the mountain land and desert/Gobi reduced K by 18.7%;therefore,once the RFP and RFS were taken into account in the calculation,K was 6.98%lower.(2)The predominant factors of the effect of RFS and the joint effect of RFP and RFS were elevation and slope *** predominant factors of the effect of RFP were annual average precipitation and annual average temperature.(3)In assessing and mapping soil erosion in large regions,special attention should be given to areas with large rock fragment contents,a relatively high altitude,and the presence of steep *** rock fragments were not taken into consideration,the mapping results of soil erosion may be *** article made the calculation of K more complete and accurate,thereby improving the accuracy of regional soil erosion *** research was of sig-nificance for the investigation of global hydrological effects and simulation of the global soil carbon budget.

关键词： Soilerosion Soil erodibility factor Rock fragment Rock cover Environmental elements

Impacts of different surface features on soil detachment in the subtropical region

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International Soil and Water Conservation Research 2021年第4期9卷 555-565页

作者： Qianhong Ma keli zhang Zihao Cao Zhicheng Yang Mengyao Wei Zaike Gu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Teacher Education Hebei Normal UniversityShijiazhuangHebei 050024China Guizhou Provincial Monitoring Station of Soil and Water Conservation GuiyangGuizhou 550002China

Near-surface features have a great influence on runoff and detachment processes by overland flow,but the contributions are still unclear on steep slopes with yellow soil in subtropical humid *** scouring experiments were conducted to investigate how near-surface features affect hydraulic parameters and detachment rate by overland *** treatments and a baseline(disturbed rootless bare cropland)were designed to identify the contributions from stem-leaves,litter,biological soil crusts(BSCs),root systems and non-disturbance,*** results showed that(1)the values of velocity,Reynolds number and Froude number for vegetated slopes were significantly lower than that of baseline,and stem-leaves made a greater contribution(average of 47.30%)to reducing kinetic energy than the other features;(2)the total contribution rate of grassland was 99.38%,and of this total,1.19,1.44,2.49,49.79 and 44.47%reductions were attributed to the stem-leaves,litter,BSCs,root systems and non-disturbance,*** system and non-disturbance dominated the detachment rate reduction;(3)with increasing flow rate or slope gradient,the total contribution rate remained between 98%and 100%;and(4)for each treatment,the relationship between detachment rate and hydraulic parameters remained constant,and the stream power was the best predictor to detachment *** study results are helpful in evaluating the effects of near-surface features on erosion control and providing reference for government decision-makers to choose appropriate soil conservation and management practices.

关键词： Vegetation Soil tillage Soil erosion Detachment rate Yellow soil

地基SAR监测的人工堆积体降雨型滑坡变形失稳分析

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山西建筑 2024年第18期50卷 73-76,89页

作者：张克利尹利洁秦宏楠北京城建勘测设计研究院有限责任公司北京100101 中国安全生产科学研究院北京100012

为了研究人工堆积松散体在降雨诱发下的变形特征,在某排土场边坡架设地基合成孔径雷达(SAR)开展全天候长期监测,基于大量监测数据分析松散堆积体的面域位移场特征,通过分析重点监测区域的时间空间演变研究人工堆积体边坡在雷达监测的失... 详细信息

为了研究人工堆积松散体在降雨诱发下的变形特征,在某排土场边坡架设地基合成孔径雷达(SAR)开展全天候长期监测,基于大量监测数据分析松散堆积体的面域位移场特征,通过分析重点监测区域的时间空间演变研究人工堆积体边坡在雷达监测的失稳特点,研究结果表明:地基SAR能够获取更全面的边坡表面位移数据,帮助掌握边坡的整体变形特征,雷达全天候的长期监测数据可以一定程度上反映降雨等各种因素对边坡变形的影响;降雨通过渗透溶蚀作用降低边坡稳定性,从而引起雷达视场中边坡表面位移变化,区域月降雨量与边坡局部变形速率而不是变形量存在正相关关系。

关键词：边坡工程变形监测地基SAR 滑坡

Hydrothermal Synthesis and Thermal Decomposition Mechanism of Alkaline Earth Benzoates

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Wuhan University Journal of Natural Sciences 1999年第1期4卷 91-96页

作者： zhang, keli Yuan, Jibing Yuan, Liangjie Sun, Jutang Wuhan University Department of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Alkaline earth benzoates were synthesized using hydrothermal reaction. The complexes were characterized by elemental analysis, IR, X ray powder diffraction. All of them are monoclinic and have layered structure. The mechanism of thermal decomposition of alkaline earth benzoates was studied by using TG, DTA, IR and gas chromatography mass spectrometry. The thermal decomposition of alkaline earth benzoates in nitrogen proceeded in one or two stages: they decomposed to form MCO 3 (M=Ca,Sr,Ba) or MgO and organic compounds, respectively. The organic compounds obtained from decomposition reaction are mainly benzophenone, triphenylmethane and so on.

关键词： alkaline earth benzoate hydrothermal reaction thermal decomposition