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Sustainable land-use patterns for arid lands: A case study in the northern slope areas of the Tianshan Mountains

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Journal of Geographical Sciences 2010年第4期20卷 510-524页

作者： LUO Geping feng yixing ZHANG Baiping CHENG Weiming Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Sustainable land use patterns are ecological and economic prerequisites of regional sustainable development. This is especially true for arid lands, where the environment is wholly fragile thanks to extremely limited precipitation, and where human activities have greatly transformed natural desert system by clearing natural vegetation, expanding oases and even building dams on inland rivers. However, the current studies on land use patterns are still characterized by field investigations and case studies, with almost no solid scientific basis. This paper holds that land types and their combination patterns are the principal basis for designing sustainable land use patterns, and that GIS and RS-based large-scale land type mapping and the study of their spatial combination structures should be coordinated with the demand of social development. The existing environmental problems induced by irrational land use mostly result from their deviation from the natural properties of land types. Taking the northern slope of the Tianshan Mountains （NSTM） as an example and considering land type patterns as the basis of land use patterns, this paper improves the vertical oa- sis-and-mid-mountain two-belts development model and the sustainable mountain land use model for arid lands put forward in recent years; and in terms of oases patterns, it outlines oasis development models, including intensive land use pattern in alluvial-diluvial fans, moderate agricultural development pattern in alluvial plains, and ecological land use pattern in river-end oases.

关键词： northern slope of the Tianshan Mountains land type land-use pattern oases

The relationship between soil,climate and forest development in the mid-mountain zone of the Sangong River watershed in the northern Tianshan Mountains,China

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Journal of Arid Land 2015年第1期7卷 63-72页

作者： Li DAI yixing feng GePing LUO YanZhong LI WenQiang XU School of Geographic and Environmental Sciences Guizhou Normal University State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

The mountainous forests in arid regions, being sensitive to climate change, are one of the key research topics related to the mechanism of interaction between climate and the terrestrial ecosystem. In this study, the spatial distribution of a mid-mountain forest and its environmental factors were investigated by using a combination of remote sensing technology, field survey, climate indices and soil nutrient analysis in the Sangong River watershed of the northern Tianshan Mountains. The forest （Picea schrenkiana） was distributed between 1,510 and 2,720 m asl. Tree height and diameter at breast height （DBH） exhibited a bi-modal pattern with increasing elevation, and rested at 2,450 and 2,250 m asl, respectively. The two maxima of DBH appeared at 2,000 and 2,550 m asl, and the taller trees were observed at 2,100 and 2,600 m asl. For the annual mean temperature, the difference was approximately 5.8℃ between the lowest and the highest limits of the forest, and the average decreasing rates per hundred meters were 0.4g℃ and 0.55℃ with increasing altitude between 1,500 and 2,000 m asl and above 2,000 m asl, respec- tively. The annual precipitation in the forest zone first increased and then decreased with the increase of altitude, and the maximum value was at 2,000 m asl. For per hundred meters, the annual precipitation increased with the rate of 31 mm between 1,500 and 2,000 m asl and decreased by 7.8 mm above 2,000 m asl. The SOM, TN and TP were high between 2,000 and 2,700 m asl and low at the lower and upper forest limits. The minimum CaCO3 con- centration, pH value and EC coincided with the maximum precipitation belt at 2,000 m asl. The SOM, TN and TP were high in the topsoil （0-10 cm） and differed significantly from the values observed in the deep soil layers （〉10 cm）. The soil nutrients exhibited spatial heterogeneity and higher aggregation in the topsoil. In conclusion, soil and climate are closely related to each other, working synergistically to determine the dev

关键词： mid-mountain forest climatic conditions soil properties Picea schrenkiana arid region central Asia

An analysis of oasis stability in arid areas:a case study in the northern slope areas of the Tianshan Mountains

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Journal of Arid Land 2009年第1期1卷 49-56页

作者： Luo, GePing Lu, Lei Yin, ChangYing feng, yixing Chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

This paper discusses oasis stability at regional scale with a case study in the northern slope areas of the Tianshan Mountains (NSTM). The results showed certain significant aspects. (1) As long as water resources in the oasis keep stable and their utilization efficiency can be maintained or gradually increased, the primary productivity could be continuously increased and the natural primary productivity keeped relatively stable. In this case, it is considered that the oasis is stable and its sustainable development can be achieved at regional scale. (2) Considering the availability of water resources in the oases, the oases on the alluvial-diluvial fans are highly stable. In the alluvial plain downstream of the groundwater overflowing zones the oases are moderately stable and in the lacustrine deltas or dry lacustrine deltas the oases are lowly stable. (3) Enlargement of oases and the increase of water resources and vegetation coverage in the oasis will certainly enhance the 'cold-island effect' of the oasis and increase the stability of oases.

关键词： oasis stability regional scale geographical location 'cold-island effect' the northern slope areas of the Tianshan Mountains

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黑色素瘤肝转移超声及临床病理特征分析

中华肿瘤杂志 2022年第4期44卷 354-359页

作者：冯一星张晟魏玺国家肿瘤临床医学研究中心天津市肿瘤防治重点实验室天津市恶性肿瘤临床医学研究中心天津医科大学肿瘤医院超声诊疗科天津300060

目的探讨黑色素瘤肝转移的超声及临床病理特征。方法选取2013—2019年于天津医科大学肿瘤医院诊治的13例黑色素瘤肝转移患者, 回顾性分析其超声及临床病理特征。结果 13例患者中, 肝转移病灶多发11例, 病灶长径为(5.89±2.73)cm。肝转... 详细信息

目的探讨黑色素瘤肝转移的超声及临床病理特征。方法选取2013—2019年于天津医科大学肿瘤医院诊治的13例黑色素瘤肝转移患者, 回顾性分析其超声及临床病理特征。结果 13例患者中, 肝转移病灶多发11例, 病灶长径为(5.89±2.73)cm。肝转移病灶为混合回声5例(黑色素高含量3例), 高回声4例(黑色素低含量3例), 低回声3例(均为黑色素高含量), 等回声1例(黑色素高含量)。肝转移病灶边界尚清11例, 边界不清2例, 病灶出现囊性区3例。肝转移病灶不规则(分叶状、小分叶状)6例, 尚规则(圆形、卵圆形)7例。病灶周边有声晕9例, 声晕为光滑、不均匀5例。免疫组化结果显示, S-100、HMB45及Melan-A均为阳性11例;1例患者未行HMB45检测, S-100及Melan-A为阳性;1例患者未行Melan-A检测, S-100及HMB45为阳性。结论黑色素瘤肝转移病灶多数为混合回声或高回声, 多数为边界清晰的结节型且伴有声晕, 少数病灶可见囊性区。

关键词：黑色素瘤肝脏转移瘤超声检查病理学

甲状腺内胸腺癌声像图特征及临床病理特点分析

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中华超声影像学杂志 2019年第3期28卷 241-245页

作者：冯一星张晟天津医科大学肿瘤医院超声诊疗科/国家肿瘤临床医学研究中心/天津市肿瘤防治重点实验室/天津市恶性肿瘤临床医学研究中心 300060

目的探讨甲状腺内胸腺癌(intrathyroid thymic carcinoma,ITTC)的声像图特征及临床病理特点。方法回顾性分析经病理证实的11例ITTC的声像图特征及临床病理特点,记录病灶的大小、形态、边界、内部回声、钙化、囊变、病灶血流及颈部淋巴... 详细信息

目的探讨甲状腺内胸腺癌(intrathyroid thymic carcinoma,ITTC)的声像图特征及临床病理特点。方法回顾性分析经病理证实的11例ITTC的声像图特征及临床病理特点,记录病灶的大小、形态、边界、内部回声、钙化、囊变、病灶血流及颈部淋巴结情况,对病灶进行TI-RADS分类,同时记录患者病史、临床症状及治疗过程。结果11例ITTC患者病灶均为实性,位于甲状腺下极或中下部分,8例位于甲状腺右叶(8/11,72.7%),3例位于甲状腺左叶(3/8,27.3%),病灶最大径线为(3.55±0.51)cm,回声均为低回声或极低回声,边界不清晰。病灶内部回声不均匀,10例肿物内部可见线样高回声。TI-RADS分类为4a类2例,4b类3例,4c类2例,5类4例。所有病灶中未出现钙化及囊性区,纵横比均<1。11例中3例同时伴有桥本甲状腺炎。手术后病理显示5例出现颈部淋巴结转移,5例侵犯周围软组织,其中3例侵犯喉返神经,2例侵犯食管壁,3例侵犯颈部横纹肌。免疫组化显示所有病灶CD5及CD117均为阳性。患者均行手术治疗,其中3例术后进行了放疗与化疗。结论ITTC有共同的声像图特征,位于甲状腺下极或者中下,呈实性低回声或极低回声,边界不清,其内可见线样高回声,这些声像图特征有助于ITTC的诊断。

关键词：超声检查甲状腺内胸腺癌病理学

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大型整体壁板加工变形控制技术研究

工具技术 2024年第3期58卷 102-106页

作者：周益星陈云邓枫胡小辉成都飞机工业(集团)有限责任公司

针对典型大型整体壁板数控加工后变形量高达40mm且无法喷丸校形的问题,采用有限元仿真研究毛坯初始残余应力与零件变形量的相关性,通过改变加工顺序,优化加工过程材料去除策略,有效控制整体壁板的加工变形。结合实际工艺方案,通过合理... 详细信息

针对典型大型整体壁板数控加工后变形量高达40mm且无法喷丸校形的问题,采用有限元仿真研究毛坯初始残余应力与零件变形量的相关性,通过改变加工顺序,优化加工过程材料去除策略,有效控制整体壁板的加工变形。结合实际工艺方案,通过合理选择切削参数,即采用小直径刀具径向逐层走刀,切削轨迹由沿宽度方向调整为沿长度方向,减少零件加工变形量。通过实例加工验证了该方法能有效解决大型整体壁板加工变形的问题。

关键词：整体壁板有限元仿真去除策略切削参数加工变形

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高熵合金纳米颗粒研究进展

中国科学：技术科学 2024年第7期54卷 1211-1245页

作者：廖怡君马艺冀连泽戎华威李逸兴张雪峰东北大学材料科学与工程学院材料各向异性与织构教育部重点实验室沈阳110819 杭州电子科技大学材料与环境工程学院先进磁性材料研究院杭州310012

当高熵合金细化至纳米尺度时,其独特的结构与纳米尺寸效应间的相互作用将赋予材料优异的功能特性.然而,由于异种元素间普遍存在的混合焓差异,将多种非混相金属稳定结合并细化至纳米尺度具有极大的理论和技术挑战.因此,本文主要综述了近... 详细信息

当高熵合金细化至纳米尺度时,其独特的结构与纳米尺寸效应间的相互作用将赋予材料优异的功能特性.然而,由于异种元素间普遍存在的混合焓差异,将多种非混相金属稳定结合并细化至纳米尺度具有极大的理论和技术挑战.因此,本文主要综述了近年来高熵合金纳米颗粒的研究进展,首先系统总结了高熵合金纳米颗粒的制备方法、合成条件以及进一步提升合金体系固溶组元数量的策略,随后从高熵合金纳米颗粒所具备的结构稳定性、氧化还原行为及异常尺寸效应等独特性质出发,对其在催化、电磁、光热、气敏和储能等领域的应用及性能机理进行了详细的分析和讨论.最后,总结展望了高熵合金纳米颗粒未来面临的挑战和发展方向.

关键词：高熵合金多组元合金纳米颗粒制备策略多功能性

间质瘤同时性肝转移与异时性肝转移超声声像图特征比较

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中华肿瘤杂志 2018年第11期40卷 829-832页

作者：冯一星张晟忻晓洁天津医科大学肿瘤医院超声诊疗科国家肿瘤临床医学研究中心天津市肿瘤防治重点实验室天津市恶性肿瘤临床医学研究中心 300060

目的探讨间质瘤肝转移的超声特点及间质瘤术后超声复查的意义。方法收集经病理证实的胃肠道间质瘤（GIST）和胃肠道外间质瘤（EGIST）患者共1 516例，其中46例发生肝转移，包括95个肝转移灶，分析肝转移灶的超声声像图特征。结果46例间... 详细信息

目的探讨间质瘤肝转移的超声特点及间质瘤术后超声复查的意义。方法收集经病理证实的胃肠道间质瘤（GIST）和胃肠道外间质瘤（EGIST）患者共1 516例，其中46例发生肝转移，包括95个肝转移灶，分析肝转移灶的超声声像图特征。结果46例间质瘤肝转移患者中，原发肿瘤位于小肠24例，胃14例，腹腔4例，食管2例，结肠1例，肠系膜1例。免疫组化CD117阳性率为100%，CD34阳性率为69.6%，Dog－1阳性率为95.7%。28例同时性肝转移和18例异时性肝转移患者原发肿瘤的最大径线、边界和血流情况差异有统计学意义（P值分别为0.001、0.022和0.036）。95个肝转移病灶中，86个（90.5%）病灶位于肝右叶，41个（43.2%）病灶≥5 cm，79个（83.2%）病灶边界清晰，75个（78.9%）病灶为低回声和中等回声，55个（57.9%）病灶可见少量或丰富血流，68个（71.6%）病灶无晕环。11个肝转移灶为囊性，59个为实性，25个为囊实性。65个同时性肝转移灶和30个异时性肝转移灶的血流情况差异有统计学意义（P＝0.017）。结论间质瘤同时性肝转移与异时性肝转移原发肿瘤超声声像图特征有差异，掌握间质瘤肝转移灶及原发肿瘤的超声声像图特征，对间质瘤伴肝转移的诊断、随访及治疗均有重要的临床意义。

关键词：胃肠道间质瘤胃肠道外间质瘤肝脏转移瘤超声

基于高内涵分析技术表征磷酸三苯酯的肺细胞毒性

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生态毒理学报 2023年第2期18卷 259-268页

作者：丰一兴王济洲段鹤君李伟红邵兵北京市疾病预防控制中心食物中毒诊断溯源技术北京市重点实验室北京100013 中国科学院大学北京100049

磷酸三苯酯(triphenyl phosphate,TPhP)是环境中最常见的有机磷酸酯阻燃剂之一,具有较强的挥发性,每天持续摄入TPhP,可能对人体肺部组织产生不利影响。本研究以人源的非小细胞肺癌细胞系(A549)为研究对象,采用高内涵分析系统检测50、100... 详细信息

磷酸三苯酯(triphenyl phosphate,TPhP)是环境中最常见的有机磷酸酯阻燃剂之一,具有较强的挥发性,每天持续摄入TPhP,可能对人体肺部组织产生不利影响。本研究以人源的非小细胞肺癌细胞系(A549)为研究对象,采用高内涵分析系统检测50、100和200μmol·L^(-1) TPhP对细胞核形态、核膜通透性、线粒体纹理结构、线粒体膜电位、细胞内氧自由基水平、磷酸化组蛋白H2AX(phosphorylated histones H2AX,pH2AX)、细胞色素C和细胞凋亡等参数的影响。结果显示,与对照组相比,随着TPhP暴露浓度的增加,A549细胞活性显著下降,细胞核面积增加、核亮度降低和核碎片化程度加剧,核膜通透性增高,细胞核的各参数在200μmol·L^(-1) TPhP组变化最显著;细胞内氧自由基水平的显著升高,进一步导致线粒体损伤和细胞色素C释放,当TPhP为100μmol·L^(-1)时,线粒体损伤程度最严重;当TPhP为100μmol·L^(-1)和200μmol·L^(-1)时,pH2AX含量显著升高,表明DNA受到损伤;100μmol·L^(-1) TPhP主要诱导细胞发生早期凋亡,而200μmol·L^(-1) TPhP诱导细胞发生早期凋亡和晚期凋亡。TPhP对人肺细胞呈现明显的细胞毒性,可引起氧化应激介导的DNA损伤和线粒体损伤,并最终导致人肺细胞发生凋亡。本研究结果为科学评估TPhP对人体健康的危害提供了数据支持和理论依据。

关键词：磷酸三苯酯人肺细胞细胞毒性表型高内涵筛选分析