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Novel Method for Evaluating the Aging of Aviation Turbine Engine Oils via High-Temperature Bearing Deposit Tests
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作者 Hao Lichun yang he +3 位作者 Song Haiqing Zhou Yunfan he Jingjian Liang Yuxiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期67-77,共11页
Aviation turbine engine oils require excellent thermal-oxidative stability because of their high-temperature environments.High-temperature bearing deposit testing is a mandatory method for measuring the thermal-oxidat... Aviation turbine engine oils require excellent thermal-oxidative stability because of their high-temperature environments.High-temperature bearing deposit testing is a mandatory method for measuring the thermal-oxidative performance of aviation lubricant oils,and the relevant apparatus was improved in the present study.Two different commercial aviation turbine engine oils were tested,one with standard performance(known as the SL oil)and the other with high thermal stability,and their thermal-oxidative stability characteristics were evaluated.After 100 h of high-temperature bearing testing,the SL oil was analyzed by using various analytical techniques to investigate its thermal-oxidative process in the bearing test,with its thermal-oxidative degradation mechanism also being discussed.The results indicate that the developed high-temperature bearing apparatus easily meets the test requirements of method 3410.1 in standard FED-STD-791D.The viscosity and total acid number(TAN)of the SL oil increased with the bearing test time,and various deposits were produced in the bearing test,with the micro-particles of the carbon deposits being sphere-like,rod-like,and sheet-like in appearance.The antioxidant additives in the oil were consumed very rapidly in the first 30 h of the bearing test,with N-phenyl-1-naphthylamine being consumed faster than dioctyldiphenylamine.Overall,the oil thermal-oxidative process involves very complex physical and chemical mechanisms. 展开更多
关键词 aviation turbine engine oil high-temperature bearing deposit test thermal-oxidative degradation antioxidant additives
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Evaluation of the Oxidation Reactivity and Behavior of Exhaust Soot Particles from Diesel Engines with Different Emission Levels
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作者 Wang Yajun Lin Lei +3 位作者 Xing Jianqiang LüXu yang he Song Haiqing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期72-80,共9页
The aim of this study was to investigate the oxidation reactivity and behavior of exhaust particulate matter(PM)from diesel engines.PM samples from two diesel engines(1K,CY4102)with different emission levels were coll... The aim of this study was to investigate the oxidation reactivity and behavior of exhaust particulate matter(PM)from diesel engines.PM samples from two diesel engines(1K,CY4102)with different emission levels were collected by a thermophoretic system and a quartz filter.The oxidation reactivity,oxidation behaviors,and physicochemical properties of the PM samples were analyzed using thermogravimetric analysis(TGA),high-resolution transmission electron microscopy(HRTEM),Fourier-transform infrared spectrometry(FTIR),and Raman spectroscopy.The results showed that there was a great difference in the oxidation reactivity of soot particles emitted by the two different diesel engines.A qualitative analysis of the factors influencing oxidation reactivity showed that the nanostructure,degree of graphitization,and relative concentration of aliphatic C—H functional groups were the most important factors,whereas no significant correlation was found between the primary particle size and activation energy of the diesel soot.Based on the oxidation behavior analysis,the diesel soot particles exhibited both internal and surface oxidation modes during the oxidation process.Surface oxidation was dominant during the initial stage,and as oxidation progressed,the mode gradually changed to internal oxidation.Internal oxidation mode of soot particles from the 1K engine was significantly higher than that of CY4102. 展开更多
关键词 diesel engine soot particles oxidation reactivity oxidation behavior
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Application of Rosemary Essential Oil in Aromatherapy from the Perspective of Traditional Chinese Medicine Theory
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作者 Meiqi Qin Yu Deng +1 位作者 Yulin Fang yang he 《Journal of Clinical and Nursing Research》 2024年第12期91-96,共6页
Aromatherapy in traditional Chinese medicine integrates the principles of traditional Chinese medicine and Western essential oil therapy,utilizing plant essential oils to regulate qi and blood,unblock meridians,and ha... Aromatherapy in traditional Chinese medicine integrates the principles of traditional Chinese medicine and Western essential oil therapy,utilizing plant essential oils to regulate qi and blood,unblock meridians,and harmonize emotions.Rosemary essential oil,a commonly used substance,exhibits anti-inflammatory,analgesic,and mood-enhancing properties.Through methods such as massage and inhalation,essential oil molecules act on the body to restore visceral balance and promote physical and mental well-being.Aromatherapy in traditional Chinese medicine offers a novel perspective for preventive medicine and is widely applied in treating various symptoms. 展开更多
关键词 Traditional Chinese medicine AROMATHERAPY Rosemary essential oil Aromatherapy of traditional Chinese medicine
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一种新的基于FPGA的HEVC帧内预测硬件结构 被引量:2
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作者 杨贺 杨秀芝 陈建 《福州大学学报(自然科学版)》 CAS 北大核心 2020年第3期318-324,共7页
在保证视频编码性能的前提下,为降低硬件实现复杂度、减少硬件资源、提高硬件的处理速度,提出一种新的基于现场可编程门阵列(FPGA)的高效视频编码标准(HEVC)帧内预测硬件结构.设计的硬件结构可以支持64×64到4×4的块大小以及... 在保证视频编码性能的前提下,为降低硬件实现复杂度、减少硬件资源、提高硬件的处理速度,提出一种新的基于现场可编程门阵列(FPGA)的高效视频编码标准(HEVC)帧内预测硬件结构.设计的硬件结构可以支持64×64到4×4的块大小以及所有的模式预测,而且经过实验,实现一个完整的64×64大小的编码树单元(CTU)的编码过程需要3.3×10^4左右的周期数,主频能够达到160 MHz. 展开更多
关键词 帧内预测 哈达玛变换 硬件结构 现场可编程门阵列
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Removal of elemental mercury from coal combustion flue gas by sodium halides impregnated red mud
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作者 MUHAMMAD Sarfraz LI yang +3 位作者 yang he JIN Lijun LI Dekang HU Haoquan 《燃料化学学报(中英文)》 北大核心 2025年第1期53-69,共17页
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi... Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations. 展开更多
关键词 mercury removal red mud sodium halides IMPREGNATION flue gas
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QuEChERS结合高效液相色谱-串联质谱法同时测定山楂中螺虫乙酯及其4种代谢物残留 被引量:4
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作者 羊河 李萌 +2 位作者 安莉 吴绪金 姚永生 《食品安全质量检测学报》 CAS 北大核心 2021年第20期8041-8048,共8页
目的建立QuEChERS结合高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)同时测定山楂(Crataegus pinnatifida Bunge.)中螺虫乙酯及其4种代谢物残留的分析方法。方法采用QuEChERS... 目的建立QuEChERS结合高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)同时测定山楂(Crataegus pinnatifida Bunge.)中螺虫乙酯及其4种代谢物残留的分析方法。方法采用QuEChERS前处理方法,样品经过1%乙酸-乙腈涡旋振荡提取及氯化钠盐析作用后,使用石墨化碳黑(graphitized carbon black,GCB)和N-丙基乙二胺(primary secondary amine,PSA)净化,经色谱柱分离,0.1%甲酸水溶液-乙腈流动相梯度洗脱。多重反应监测模式下,高效液相色谱-串联质谱法测定,基质匹配标准溶液的外标法定量。结果螺虫乙酯及其代谢产物在0.005~0.500 mg/L范围内呈良好的线性关系,相关系数r^(2)大于0.98,最低检测浓度为0.01 mg/kg。当添加水平为0.01、0.10、1.00 mg/kg时,山楂中螺虫乙酯及其代谢产物的平均回收率为83%~106%,相对标准偏差(relative standard deviations,RSDs)为0.6%~11.0%。结论该方法操作简单快捷、反应灵敏、重现性好,符合NY/T 788—2018《农作物中农药残留试验准则》的要求,适用于测定山楂中螺虫乙酯及其代谢产物残留。 展开更多
关键词 螺虫乙酯 代谢物 山楂 QUECHERS 高效液相色谱-串联质谱法
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新辅助化疗对乳腺癌ER PR HER-2及Ki-67表达影响的研究进展 被引量:21
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作者 何洋 赵伟鹏(综述) 佟仲生(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第22期1185-1188,共4页
目前乳腺癌已成为女性发病率最高的恶性肿瘤,新辅助化疗(neoadjuvant chemotherapy,NAC)后雌激素受体(estrogen re-ceptor,ER)、孕激素受体(progesterone receptor,PR)和人表皮生长因子受体-2(human epidermal growth factor receptor-2... 目前乳腺癌已成为女性发病率最高的恶性肿瘤,新辅助化疗(neoadjuvant chemotherapy,NAC)后雌激素受体(estrogen re-ceptor,ER)、孕激素受体(progesterone receptor,PR)和人表皮生长因子受体-2(human epidermal growth factor receptor-2,HER-2)、Ki-67表达情况会有不同程度变化,这种变化机制是否会影响后续治疗方案的选择尚无定论。本文将就NAC对乳腺癌ER、PR、HER-2及Ki-67表达影响的研究进展进行综述。 展开更多
关键词 乳腺癌 新辅助化疗 雌激素 孕激素 人表皮生长因子受体-2 Ki-67
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Effects of dietary fiber on human health 被引量:20
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作者 yang he Bixiang Wang +5 位作者 Liankui Wen Fengzhong Wang Hansong Yu Dongxia Chen Xin Su Chi Zhang 《Food Science and Human Wellness》 SCIE 2022年第1期1-10,共10页
Dietary fiber(DF)is believed to provide important health benefits and it has become a research hotspot.DF exists in most natural foods,including fruits(16.74%-91.24%),vegetables(6.53%-85.19%),grains(9.76%-69.20%)and s... Dietary fiber(DF)is believed to provide important health benefits and it has become a research hotspot.DF exists in most natural foods,including fruits(16.74%-91.24%),vegetables(6.53%-85.19%),grains(9.76%-69.20%)and so on.DF has different physicochemical properties such as water holding capacity(WHC)(2.01-25.03 g/g),water swelling capacity(WSC)(0.95-23.90 mL/g),oil holding capacity(OHC)(0.65-29.00 g/g),glucose adsorption capacity(GAC)(0.17-4.65 mmol/g),cholesterol adsorption capacity(CAC)(0.03-37.10 mg/g)and viscosity,which make it exhibits different physiological functions such as reducing the risk of obesity,diabetes,cancer,and intestinal diseases.On the basis of consulting related databases,the physicochemical properties of DF and its derived physiological functions are reviewed.It is found that DF has effect on the prevention and treatment of obesity due to good WHC,WSC,OHC and CAC.Good GAC can relieve the symptoms of diabetes.The physicochemical properties of WHC and WSC can reduce the risk of cancer.The WHC,WSC and viscosity are beneficial to intestinal health. 展开更多
关键词 Dietary fiber Physicochemical properties Human health
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Treatment of the acute thromboembolic event during endovascular embolization of intracranial aneurysm 被引量:13
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作者 Bing Zhou yang he +5 位作者 Jun Cheng XiaoDong Lu MingZhao Zhang Bo Li RongQing Qin ZhongMing Gao 《Journal of Interventional Medicine》 2020年第4期208-212,共5页
Objective:The study aimed to discuss the treatment of acute thromboembolic event(TE)during endovascular embolization of intracranial aneurysms.Methods:Between April 2013 and April 2019,158 patients with 167 intracrani... Objective:The study aimed to discuss the treatment of acute thromboembolic event(TE)during endovascular embolization of intracranial aneurysms.Methods:Between April 2013 and April 2019,158 patients with 167 intracranial aneurysms were treated with endovascular embolization in our hospital,in which 9 cases of acute TEs occurred during the embolization procedures.The clinical data,radiological findings and treatments of the 9 patients were reviewed and analyzed.Results:The TEs occurred at the aneurysmal neck in 3 patients,at distal part of the parent artery in 3,in the stent in 2,and at the proximal part of the parent artery in 1.Intra-arterial(IA)infusion of tirofiban were performed in 6 patients,mechanical thromboectomy(MT)with a stent in 2 patients,and combined use of the two methods in 1 patients.According to the modified Thrombolysis In Cerebral Infarction(mTICI)score,7 patients had recanalization of 2b/3a,1 patients had recanalization of 1,and 1 patients had recanalization of 0.At discharge,the mRS score was 0 in 3 patients,1 in 3 patients,and 2,3,4 in 1 patient each.6 months after the endovascular treatment,the mRS score was 0 in 5 patients,1 in 2 patients,and 3 in 1 patient.Conclusions:IA tirofiban and MT are effective remedies for the acute TE during endovascular embolization of intracranial aneurysm,reasonable selection of which may improve the prognosis of patients. 展开更多
关键词 ANEURYSM EMBOLIZATION Mechanical thromboectomy MT Thromboembolic event TE Intra-arterial IA
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The association between the baseline bone resorption marker CTX and incident dysglycemia after 4 years 被引量:10
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作者 Ting-ting Liu Dong-mei Liu +11 位作者 Yan Xuan Lin Zhao Li-hao Sun Dian-dian Zhao Xiao-feng Wang yang he Xing-Zhi Guo Rui Du Ji-qiu Wang Jian-min Liu Hong-yan Zhao Bei Tao 《Bone Research》 SCIE CAS CSCD 2017年第3期235-241,共7页
Bone is an endocrine organ involved in modulating glucose homeostasis. The role of the bone formation marker osteocalcin (OCN) in predicting diabetes was reported, but with conflicting results. No study has explored... Bone is an endocrine organ involved in modulating glucose homeostasis. The role of the bone formation marker osteocalcin (OCN) in predicting diabetes was reported, but with conflicting results. No study has explored the association between baseline bone resorption activity and incident diabetes or prediabetes during follow-up. Our objective was to examine the relationship between the baseline bone resorption marker crosslinked C-telopeptide of type I collagen (CTX) and glycemic dysregulation after 4 years. This longitudinal study was conducted in a university teaching hospital. A total of 195 normal glucose tolerant (NGT) women at baseline were invited for follow-up. The incidence of diabetes and prediabetes (collectively defined as dysglycemia) was recorded. A total of 128 individuals completed the 4-year study. The overall conversion rate from NGT to dysglycemia was 31.3%. The incidence of dysglycemia was lowest in the middle tertile [16.3% (95% confidence interval (CI), 6.8%-30.70/0)] compared with the lower [31.0% (95% CI, 17.2%-46.1%)] and upper [46.5% (95% CI, 31.2%-62.6%)] tertiles of CTX, with a significant difference seen between the middle and upper tertiles (P = 0.002 5). After adjusting for multiple confounding variables, the upper tertile of baseline CTX was associated with an increased risk of incident dysglycemia, with an odds ratio of 7.09 (95% CI, 1.73-28.99) when the middle tertile was the reference. Osteoclasts actively regulate glucose homeostasis in a biphasic model that moderately enhanced bone resorption marker CTX at baseline provides protective effects against the deterioration of glucose metabolism, whereas an overactive osteoclastic function contributes to an increased risk of subsequent dysglycemia. 展开更多
关键词 CTX The association between the baseline bone resorption marker CTX and incident dysglycemia after 4 years
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意向性牙再植术保留重度牙周炎患牙的临床应用策略 被引量:1
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作者 叶畅畅 杨禾 黄萍 《华西口腔医学杂志》 CAS CSCD 北大核心 2024年第1期12-18,共7页
随着牙周组织再生技术的发展与进步,越来越多的学者报道可通过意向性牙再植术治疗重度牙周炎患牙。对于已经具备拔牙指征的重度牙周炎患牙,意向性牙再植术已经成为保存天然牙最后的可能手段。然而意向性牙再植术的适应证要求严格,手术... 随着牙周组织再生技术的发展与进步,越来越多的学者报道可通过意向性牙再植术治疗重度牙周炎患牙。对于已经具备拔牙指征的重度牙周炎患牙,意向性牙再植术已经成为保存天然牙最后的可能手段。然而意向性牙再植术的适应证要求严格,手术能否成功与病例的选择和医生的操作技能密不可分。本文探讨意向性牙再植术治疗重度牙周炎患牙的适应证和操作步骤,并结合文献和病例分析影响重度牙周炎患牙意向性牙再植术预后的相关因素,为临床医生了解和掌握该项手术技术提供参考。 展开更多
关键词 意向性牙再植术 重度牙周炎 保存天然牙
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Diurnal expression of circadian clock genes period 1 and period 3 in Pelteobagrus vachellii 被引量:2
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作者 Chuanjie QIN Ting SHAO +3 位作者 Xufeng LIAO yang he Jun WANG Peng HU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期652-660,共9页
Circadian clock genes are crucial for generating and sustaining most rhythmic daily functions in the animal kingdom,which entrain the rhythms of biochemical,physiological,and behavioural processes.To better understand... Circadian clock genes are crucial for generating and sustaining most rhythmic daily functions in the animal kingdom,which entrain the rhythms of biochemical,physiological,and behavioural processes.To better understand the molecular oscillations of the circadian rhythms in darkbarbel catfish(Pelteobagrus vachellii),we isolated and characterized two circadian clock genes in P.vachellii,period 1(per1),and period 3(per3).The circadian clock gene per1 was found to encode a 1428-amino acid polypeptide,including PER-ARNT-SIM(PAS)dimerisation domains,a PAS-associated C-terminal motif(PAC),a short mutable domain(S/M),and a nuclear export signal(NES).The 4902-bp per3 cDNA includes an open reading frame encoding a 1292-amino acid residue polypeptide with a PER-ARNT-SIM(PAS)domain,cytoplasmic localisation domain(CLD),interaction site(TIS),and a nuclear localisation signal(NLS).The per1 and per3 gene was constitutively expressed in all examined tissues.Moreover,per1 expression within a light/dark cycles showed rhythmic expression in the diencephalon,brain,liver and intestine,with the acrophase at 15:15,12:52,7:51 and 12:55,respectively.Daily expression of per3 was rhythmic in the diencephalonbrain,liver and intestine,with the acrophase at 8:15,9:54,10:39,and 10:25 h,respectively.These findings expand our understanding of circadian mechanism at the molecular level in this species. 展开更多
关键词 CDNA circadian rhythm diurnal expression Pelteobagrus vachellii period 1 period 3
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The Role of Diesel Soot in the Tribological Behavior of 150SN Base Oil 被引量:2
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作者 Su Peng Xiong Yun +3 位作者 Liu Xiao yang he Fan Linjun Liu Ping 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第2期89-95,共7页
The diesel soot was collected from diesel engine exhaust pipe. The morphology and structure of the collected diesel soot was characterized by HRTEM, XRD and XPS and its tribological behavior was investigated by a SRV ... The diesel soot was collected from diesel engine exhaust pipe. The morphology and structure of the collected diesel soot was characterized by HRTEM, XRD and XPS and its tribological behavior was investigated by a SRV IV oscillating reciprocating friction and wear tester. Test results showed that the tribological behavior of diesel soot was largely influenced by the test load. Under a low load, the diesel soot could reduce the wear volume of the disc. While under a high load, the diesel soot could reduce the friction coefficient of base oil. Based on the characterization of the worn scars by the SEM technique, the 3D surface profiler and the Raman spectroscopy, it was assumed that the core-shell structure of diesel soot with several graphitic layers played important roles. On one hand, its spherical and special structure could make it roll between friction pairs to reduce wear under a low load. On the other hand, its outer-shell graphite layers could be peeled off to form lubrication film to reduce friction under a high load and shear force. 展开更多
关键词 DIESEL SOOT TRIBOLOGICAL behavior CORE-SHELL structure 150SN BASE OIL
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Spatial Pattern and Development of Protected Areas in the North-south Transitional Zone of China 被引量:1
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作者 LI Xiang MA Beibei +2 位作者 LU Chunxia yang he SUN Mengyu 《Chinese Geographical Science》 SCIE CSCD 2021年第1期149-166,共18页
The north-south transitional zone in China mainly consists of the Qinling-Daba Mountains. It is the most important West-East geo-ecological space in China, containing protected areas vital for biodiversity conservatio... The north-south transitional zone in China mainly consists of the Qinling-Daba Mountains. It is the most important West-East geo-ecological space in China, containing protected areas vital for biodiversity conservation and ecological security of China. The protection and rational development of its natural habitat is of great significance to China’s ecological security and integration of protected areas based on mountain forest ecosystems on a global scale. In this study, five important types of protected areas in the transitional zone were selected, and their spatial patterns were analysed. Spatial analysis methods, such as kernel density estimation and accessibility analysis, were employed for both point and areal data, and focused on four aspects: land use scale, shift in the centre of gravity, spatial agglomeration, and accessibility. In addition, policy background and evolution of spatial and temporal characteristics of the protected area system in the transitional zone from 1963 to 2017 were also examined. We analysed the characteristics and geographical significance of the West-east corridor using the spatial pattern of the protected area system from the perspective of ecological and economic spaces. We focused on spatial shape, type intersection, and key areas to analyse the spatial overlap of the protected areas. Protected area establishment was divided into three stages: initial(1956–1980), rapid development(1981–2013), and national park transformation(2014–present). These stages reflected the change in the concept of ‘simple protection—sustainable use—integration and upgrade’ for protected areas of China. The spatial centre of gravity of the protection zone system was located in the west Qinling-Daba Mountains, and its high-density core exhibited a relatively stable N-shaped structure composed of four gathering areas. Affected by factors such as geographic environment and socio-economic development density, the average access time for protected areas was high(1.56 h);wetland parks and scenic areas are located closer to the city centre. As the West-east corridor in the transitional zone extends from west to east, there is a clear spatial dislocation between the development of protected areas and the intensity of human activities. During development, differentiated goal orientation should be adopted based on the idea of zoning and classified governance. With the advancement of the construction of protected areas, the spatial overlap of protected areas in the transition zone has become more prominent. At present, the spatially overlapped protected areas in the transitional zone remain prominent, with inclusion overlap being the most common, and forest parks exhibiting the highest probability of overlap with other protected areas, we should focus on in the integration process of the corridor-type ecological space based on the mountain forest ecosystem. 展开更多
关键词 North-south Transitional Zone(NSTZ) protected area(PA) spatial-temporal pattern ACCESSIBILITY the West-east corridor spatial overlap
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Carbothermal reduction characteristics of oxidized Mn ore through conventional heating and microwave heating 被引量:1
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作者 yang he Jian Liu +2 位作者 Jian-hua Liu Chun-lin Chen Chang-lin Zhuang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第2期221-230,共10页
For the purpose of exploring a potential process to produce FeMn,the effects of microwave heating on the carbothermal reduction characteristics of oxidized Mn ore was investigated.The microwave heating curve of the mi... For the purpose of exploring a potential process to produce FeMn,the effects of microwave heating on the carbothermal reduction characteristics of oxidized Mn ore was investigated.The microwave heating curve of the mixture of oxidized Mn ore and coke was analyzed in association with the characterization of dielectric properties.The comparative experiments were conducted on the carbothermal reductions through conventional and microwave heatings at temperatures ranging from 973 to 1373 K.The thermogravimetric analysis showed that carbothermal reactions under microwave heating proceeded to a greater extent and at a faster pace compared with those under conventional heating.The metal phases were observed in the microstructures only under microwave heating.The carbothermal reduction process under microwave heating was discussed.The electric and magnetic susceptibility differences were introduced into the thermodynamics analysis for the formation of metal Mn.The developed thermodynamics considered that microwave heating could make the reduction of MnO to Mn more accessible and increase the reduction extent. 展开更多
关键词 carbothermal reduction manganese ore manganese oxides microwave heating THERMODYNAMICS electromagnetic fields
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Episodic Paleozoic Adakitic Magmatism in the Eastern Tianshan,Southern Altaids:Implications for Petrogenesis and Geodynamics 被引量:1
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作者 WANG Meng XIAO Wenjiao +3 位作者 MAO Qigui yang he WANG Hao LI Rui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第4期1136-1149,共14页
The adakites rocks are typically considered as direct diagnostic evidence for subduction and continental growth,as well as the important evidence to determine the location of the major oceanic basin and evolution hist... The adakites rocks are typically considered as direct diagnostic evidence for subduction and continental growth,as well as the important evidence to determine the location of the major oceanic basin and evolution history of lost oceanic basins,which are longstanding conundrums for understanding the tectonics of the Paleo-Asian Ocean(PAO).As the processor of the Altaids,the PAO was a long-lived ocean,and its multiple subductions led to substantial continental growth in the Central Asian continent.Here we report our newly discovered Paleozoic adakitic rocks(granite and dacite)developed in Jijitaizi in the Eastern Tianshan of the southern Altaids to address the above issues.The Jijitaizi granite and dacite contain high concentrations of Sr(203-343 ppm)and low concentrations of Y(3.00-6.36 ppm)and Yb(0.23-0.62 ppm),indicative of the adakitic affinity.Zircon U-Pb dating results show that the adakitic rocks were formed in three episodes at 372.26±1.51 Ma,356.02±1.11 Ma and 334.51±0.68 Ma from the Late Devonian to Carboniferous.The rocks are depleted in Nb,P and Ti,and possess variable Mg#values(28.51-57.22),high Na_(2)O/K_(2)O ratios(1.39-4.94),as well as relatively depleted Hf isotopic compositions,all of which point to a subduction origin from slab melting.Our new finding with the date from the Jijitaizi complex(ca.321 Ma)suggests continuing subduction of the Paleo-Asian oceanic slab beneath the Central Tianshan from the Late Devonian to Carboniferous.Our work provides a solid line of key evidence demonstrating that continuous oceanic subduction of the major PAO evolved into its mature stage following subducting beneath the Central Tianshan from ca.372 to 321 Ma. 展开更多
关键词 ADAKITE Paleo-Asian Ocean Eastern Tianshan CAOB Multiple subduction
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Atmospheric Disturbance Characteristics in the Lower-middle Stratosphere Inferred from Observations by the Round-Trip Intelligent Sounding System(RTISS)in China 被引量:1
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作者 yang he Xiaoqian ZHU +3 位作者 Zheng SheNG Wei GE Xiaoran ZHAO Mingyuan he 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第1期131-144,共14页
Through multi-order structure function analysis and singularity measurement,the Hurst index and intermittent parameter are obtained to quantitatively describe the characteristics of atmospheric disturbance based on th... Through multi-order structure function analysis and singularity measurement,the Hurst index and intermittent parameter are obtained to quantitatively describe the characteristics of atmospheric disturbance based on the round-trip intelligent sounding system(RTISS)in the lower-middle stratosphere.According to the third-order structure function,small-scale gravity waves are classified into three states:stable,unstable,and accompanied by turbulence.The evolution of gravity waves is reflected by the variation of the third-order structure function over time,and the generation of turbulence is also observed.The atmospheric disturbance intensity parameter RT is defined in this paper and contains both wave disturbance(H_(1))and random intermittency(C_(1)).RT is considered to reflect the characteristics of atmospheric disturbance more reasonably than either of the above two alone.In addition,by obtaining the horizontal wavenumber spectrum from the flat-floating stage and the vertical wavenumber spectrum from the ascending and descending stages at the height range of18-24 km,we found that when the gravity wave activity is significantly enhanced in the horizontal direction,the amplitude of the vertical wavenumber spectrum below is significantly larger,which shows a significant impact of gravity wave activity on the atmospheric environment below. 展开更多
关键词 structure function TURBULENCE gravity wave in-situ detection
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Review:Recent Progress on Poly(ether ether ketone) and Its Composites for Biomedical, Machinery, Energy and Aerospace Applications 被引量:1
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作者 Shuai yang yang he Jinsong Leng 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第3期243-258,共16页
Poly(ether ether ketone)(PEEK)has drown researchers’wide attention because of the exceptional performances such as mechanical properties,thermal stability,chemical resistance,and biocompatibility.These properties end... Poly(ether ether ketone)(PEEK)has drown researchers’wide attention because of the exceptional performances such as mechanical properties,thermal stability,chemical resistance,and biocompatibility.These properties endow it with broad potential use in biomedical,engineering,and aerospace applications.In addition,multifunctional fillers have been intensively incorporated into PEEK matrix,as it is conducive to the enhanced properties,and has the desired properties in concrete applications.This review introduced the basic content and synthesis pathway of PEEKs and their composites,focusing on the various applications,including biomedical,machinery,energy storage,and aerospace applications.Considerable efforts have been devoted to explore the concrete modified method to obtain the desired performances of PEEK based materials.At the end,existing problems and development directions for the PEEK based materials were analyzed and predicted. 展开更多
关键词 poly(ether ether ketone) applied patterns biomedical applications machinery engineering aerospace applications
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Cu/Ce负载对赤泥脱除中低温烟气中NO的促进作用
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作者 李扬 徐博 +2 位作者 杨赫 靳立军 胡浩权 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第3期362-372,共11页
本研究对酸洗赤泥催化剂进行Cu、Ce、Cu/Ce浸渍负载,并研究了金属改性赤泥对烟气中NOx的催化转化性能。研究结果表明,Cu负载催化剂中的Cu+与Cu^(2+),有效促进了赤泥对低温烟气(200–300℃)中的NO转化率,Cu的负载量达到6%时,赤泥的最高N... 本研究对酸洗赤泥催化剂进行Cu、Ce、Cu/Ce浸渍负载,并研究了金属改性赤泥对烟气中NOx的催化转化性能。研究结果表明,Cu负载催化剂中的Cu+与Cu^(2+),有效促进了赤泥对低温烟气(200–300℃)中的NO转化率,Cu的负载量达到6%时,赤泥的最高NO转化率达到了90.7%;而Ce负载催化剂中的Ce^(3+)与Ce^(4+),有效促进了赤泥对中温烟气(200–400℃)中的NO转化率,Ce的负载量达到8%时,赤泥的最高NO转化率达到了94.0%;Cu/Ce负载催化剂表现出比单金属负载催化剂更好的低温NO转化率,最佳的负载Cu:Ce比例为1∶1,双金属负载催化剂表现出比Cu负载催化剂更好的中温(300–400℃)中的NO转化率,最高达到了95.5%。其原因是,在Cu/Ce协同作用下,Cu+以及Cu^(2+)的还原过程分别从229、302℃降至201以及247℃,同时使发生Fe2O3→FeO的还原过程的温度降低,促使ACRM-Cu1Ce1具有更强的低温氧化还原能力,同时,双金属负载使催化剂具有更高的弱酸性峰,也使催化剂的强、弱酸性峰都向低温偏移,并使负载后的赤泥具有了较高的Fe离子平均氧化态以及较高的Cu+含量,促进了赤泥催化剂对低温NO的转化率。 展开更多
关键词 赤泥 SCR CU CE 负载
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The Construction of Human Resource Management Cloud Service Platform 被引量:1
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作者 Liangtie Dai yang he Guangdong Xing 《Intelligent Information Management》 2015年第1期1-6,共6页
Human resource management service faced the challenges of promoting efficiency, costs saving, quick responding and so on. In order to face these challenges, this paper puts forward a “6 + 1” structure of human resou... Human resource management service faced the challenges of promoting efficiency, costs saving, quick responding and so on. In order to face these challenges, this paper puts forward a “6 + 1” structure of human resource management service combined with some characteristics of cloud computing, elaborates the service mode of the cloud service platform based on this structure, the characteristics and challenges of the platform, and hopes to provide a new service perspective to human resource management. 展开更多
关键词 Human RESOURCE Management CLOUD SERVICE PLATFORM Structure SERVICE MODE
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