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Meter-scale variation within a single transect demands attention to taxon accumulation curves in riverine

《环境科学与工程前沿（英文）》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1543-6

摘要：

● Riverine microbiomes exhibited hyperlocal variation within a single transect.

关键词： Microbiome     Freshwater     Taxon accumulation curve     Community assembly    

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Erratum to: Meter-scale variation within a single transect demands attention to taxon accumulation curves

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-022-1560-5

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Is there an inverted U-shaped curve?Empirical analysis of the Environmental Kuznets Curve in agrochemicals

Fei LI,Suocheng DONG,Fujia LI,Libiao YANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 276-287 doi: 10.1007/s11783-014-0700-y

摘要： As the largest contributor to water impairment, agriculture-related pollution has attracted the attention of scientists as well as policy makers, and quantitative information is being sought to focus and advance the policy debate. This study applies the panel unit root, heterogeneous panel cointegration, and panel-based dynamic ordinary least squares to investigate the Environmental Kuznets Curve on environmental issues resulting from use of agricultural synthetic fertilizer, pesticide, and film for 31 provincial economies in mainland China from 1989 to 2009. The empirical results indicate a positive long-run co-integrated relationship between the environmental index and real GDP per capita. This relationship takes on the inverted U-shaped Environmental Kuznets Curve, and the value of the turning point is approximately 10,000–13,000, 85,000–89,000 and over 160,000 CNY, for synthetic fertilizer nitrogen indicator, fertilizer phosphorus indicator and pesticide indicator, respectively. At present, China is subject to tremendous environmental pressure and should assign more importance to special agriculture-related environmental issues.

关键词： Environmental Kuznets Curve     agrochemical     China    

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Genotype variations in accumulation of cadmium and lead in celery (

Kun ZHANG, Jianbing WANG, Zhongyi YANG, Guorong XIN, Jiangang YUAN, Junliang XIN, Charlie HUANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 85-96 doi: 10.1007/s11783-012-0399-3

摘要： To help reduce risks of heavy metal pollution, two pot experiments were conducted to investigate the variations, transfer potential, and stability of Cadmium (Cd) and Lead (Pb) accumulations in celery ( L.) and to screen for low Cd and Pb accumulative cultivars. The maximum differences in shoot Cd concentration were 4.7-fold under low-Cd exposure and 3.3-fold under high-Cd exposure. These genotype variations in Cd accumulation are sufficiently large to help reduce Cd contamination risk in soil by using the Low-Cd-Accumulative genotypes. Cd accumulation of the Low-Cd-Accumulative genotypes is significantly positive correlated with Pb accumulation. Evidence obtained proves that Cd and Pb accumulations in celery are stable and genotype-dependent at the cultivar level. The presence of high-Pb contamination in soil promoted Cd accumulation in shoots of celery. Celery is considered a species with high risks in Cd pollution and low risks in Pb pollution. Among the tested cultivars, cv. Shuanggangkangbing (SGKB) had the lowest shoot Cd and Pb accumulating abilities, and thus is the most important material for breeding of pollution-safe cultivars (PSCs) to minimize Cd and Pb accumulations in celery.

关键词： cadmium (Cd) accumulation     lead (Pb) accumulation     celery     genotype variation     food safety    

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Learning curve of totally thoracoscopic pulmonary segmentectomy

Weibing Wu, Jing Xu, Wei Wen, Yue Yu, Xinfeng Xu, Quan Zhu, Liang Chen

《医学前沿（英文）》 2018年 第12卷 第5期   页码 586-592 doi: 10.1007/s11684-017-0566-z

摘要：

Totally thoracoscopic pulmonary segmentectomy (TTPS) is a feasible and safe technique that requires advanced thoracoscopic skills and knowledge of pulmonary anatomy. However, data describing the learning curve of TTPS have yet to be obtained. In this study, 128 patients who underwent TTPS between September 2010 and December 2013 were retrospectively analyzed to evaluate the learning curve and were divided chronologically into three phases, namely, ascending phase (A), plateau phase (B), and descending phase (C), through cumulative summation (CUSUM) for operative time (OT). Phases A, B, and C comprised 39, 33, and 56 cases, respectively. OT and blood loss decreased significantly from phases A to C (P <0.01), and the frequency of intraoperative bronchoscopy for target bronchus identification decreased gradually (A, 8/39; B, 4/33; C, 3/56; P = 0.06). No significant differences were observed in demographic factors, conversion, complications, hospital stay, and retrieved lymph nodes among the three phases. Surgical outcomes and techniques improved with experience and volume. CUSUMOT indicated that the learning curve of TTPS should be more than 72 cases.

关键词： thoracoscopic     segmentectomy     learning curve     CUSUM    

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Comparison of growth and lipid accumulation properties of two oleaginous microalgae under different nutrient

Qiao ZHANG,Yu HONG

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 703-709 doi: 10.1007/s11783-014-0649-x

摘要： This study compared the growth and lipid accumulation properties of two oleaginous microalgae, namely, sp. LX1 and sp. HQ, under different nutrient conditions. Both algal species obtained the highest biomass, lipid content and lipid yield under low-nutrient conditions (mBG11 medium). The biomass, lipid content and lipid yield of sp. LX1 were 0.42 g·L , 22.5% and 93.8 mg·L , respectively. These values were relatively higher than those of sp. HQ (0.30 g·L , 17.1% and 51.3 mg·L , respectively). These algae were then cultivated in an SE medium that contained more nutrients; as a result, the biomass and lipid yield of sp. LX1 reduced more significantly than those of sp. HQ. Opposite results were observed in lipid and triacylglycerols (TAGs) contents. The cell sizes of both algal species under low-nutrient conditions were larger than those under high-nutrient conditions. sp. HQ cells did not aggregate, but sp. LX1 cells flocculated easily, particularly under low-nutrient conditions. In summary, low-nutrient conditions favour the growth and lipid production of both algae, but sp. LX1 outperforms sp. HQ.

关键词： Scenedesmus sp. LX1     Chlorella sp. HQ     growth rate     algal biomass     lipid accumulation     triacylglycerols (TAGs)    

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Experimental study of nitrite accumulation in pre-denitrification biological nitrogen removal process

WU Xuelei, CHEN Lunqiang, PENG Yongzhen, WANG Pu, WANG Yayi

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 236-240 doi: 10.1007/s11783-008-0008-x

摘要： The effect of dissolved oxygen (DO) concentration on nitrite accumulation was investigated in a pilot-scale pre-denitrification process at room temperature for 100 days. In the first 10 days, due to the instability of the system, the DO concentration fluctuated between 1.0 and 2.0 mg/L. In the next 14 days, the DO concentration was kept at 0.5 mg/L and nitrite accumulation occurred, with the average nitrite accumulation rate at 91%. From the 25th day, the DO concentration was increased to 2.0 mg/L to destroy the nitrite accumulation, but nitrite accumulation rate was still as high as 90%. From the 38th day the nitrite accumulation rate decreased to 15%–30% linearly. From the 50th day, DO concentration was decreased to 0.5 mg/L to resume nitrite accumulation. Until the 83rd day the nitrite accumulation rate began to increase to 80%. Dissolved oxygen was the main cause of nitrite accumulation, taking into account other factors such as pH, free ammonia concentration, temperature, and sludge retention time. Because of the different affinity for oxygen between nitrite oxidizing bacteria and ammonia oxidizing bacteria when DO concentration was kept at 0.5 mg/L, nitrite accumulation occurred.
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Numerical investigation of circle defining curve for two-dimensional problem with general boundaries

Chung Nguyen VAN

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 92-102 doi: 10.1007/s11709-018-0472-8

摘要： The scaled boundary finite element method (SBFEM) is applied to the static analysis of two dimensional elasticity problem, boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force, general boundary conditions, and bounded and unbounded domain. This paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining curve. Three linear elasticity problems are presented to verify the proposed method with the analytical solution. Numerical examples show the accuracy and efficiency of the proposed method, and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry     circular defining curve     general boundaries     SBFEM    

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Simultaneous denitrifying phosphorus accumulation in a sequencing batch reactor

YUAN Linjiang, HAN Wei, WANG Lei, YANG Yongzhe, WANG Zhiying

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 23-27 doi: 10.1007/s11783-007-0004-6

摘要： In order to achieve simultaneous nitrogen and phosphorus removal in the biological treatment process, denitrifying phosphorus accumulation (DNPA) and its affecting factors were studied in a sequencing batch reactor (SBR) with synthetic wastewater. The results showed that when acetate was used as the sole carbon resource in the influent, the sludge acclimatized under anaerobic/aerobic operation had good phosphorus removal ability. Denitrifying phosphorus accumulation was observed soon when fed with nitrate instead of aeration following the anaerobic stage, which is a vital premise to DNPA. If DNPA sludge is fed with nitrate prior to the anaerobic stage, the DNPA would weaken or even disappear. At the high concentration of nitrate fed in the anoxic stage, the longer anoxic time needed, the better the DNPA was. Induced DNPA did not disappear even though an aerobic stage followed the anoxic stage, but the shorter the aerobic stage lasted, the higher the proportions of phosphorus removal via DNPA to total removal.

关键词： SBR     synthetic wastewater     Induced DNPA     resource     removal ability    

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Comparisons in subcellular and biochemical behaviors of cadmium between low-Cd and high-Cd accumulation

Meng XUE, Yihui ZHOU, Zhongyi YANG, Biyun LIN, Jiangang YUAN, Shanshan WU

《环境科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 226-238 doi: 10.1007/s11783-013-0582-4

摘要： Subcellular distributions and chemical forms of cadmium (Cd) in the leaves, stems and roots were investigated in low-Cd accumulation cultivars and high-Cd accumulation cultivars of pakchoi ( L.). Root cell wall played a key role in limiting soil Cd from entering the protoplast, especially in the low-Cd cultivars. The high-Cd cultivars had significantly higher leaf and stem Cd concentrations than the low-Cd cultivars in cell wall fraction, chloroplast/trophoplast fraction, organelle fraction and soluble fraction. In low-Cd cultivars, which were more sensitive and thus had greater physiological needs of Cd detoxification than high-Cd cultivars, leaf vacuole sequestrated higher proportions of Cd. Cd in the form of pectate/protein complexes (extracted by 1 mol·L NaCl) played a decisive role in Cd translocation from root to shoot, which might be one of the mechanisms that led to the differences in shoot Cd accumulation between the two types of cultivars. Furthermore, the formation of Cd-phosphate complexes (extracted by 2% HAc) was also involved in Cd detoxification within the roots of pakchoi under high Cd stress, suggesting that the mechanisms of Cd detoxification might be different between low- and high-Cd cultivars.

关键词： cadmium (Cd)     low-Cd cultivar     pakchoi (Brassica chinensis L.)     subcellular distribution     chemical forms    

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Heavy metal accumulation and phytostabilization potential of dominant plant species growing on manganese

YANG Shengxiang,LIANG Shichu,YI Langbo,XU Bibo,CAO Jianbing,GUO Yifeng,ZHOU Yu

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 394-404 doi: 10.1007/s11783-013-0602-4

摘要： Screening plants that are hypertolerant to and excluders of certain heavy metals plays a fundamental role in a remediation strategy for metalliferous mine tailings. A field survey of terrestrial higher plants growing on Mn mine tailings at Huayuan, Hunan Province, China was conducted to identify candidate species for application in phytostabilization of the tailings in this region. In total, 51 species belonging to 21 families were recorded and the 12 dominant plants were investigated for their potential in phytostabilization of heavy metals. Eight plant species, , , , , , , , and accumulated much lower concentrations of heavy metals in shoots and roots than the associated soils and bioconcentration factors (BFs) for Cd, Mn, Pb and Zn were all<1, demonstrating a high tolerance to heavy metals and poor metals translocation ability. The field investigation also found that these species grew fast, accumulated biomass rapidly and developed a vegetation cover in a relatively short time. Therefore, they are good candidates for phytostabilization purposes and could be used as pioneer species in phytoremediation of Mn mine tailings in this region of South China.

关键词： Mn mine tailings     heavy metal accumulation     phytostabilization    

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学习曲线及在工业生产运作研究中的应用综述

陈志祥

《中国工程科学》 2007年 第9卷 第7期   页码 82-88

摘要：

学习曲线是一种通过生产者行为学习与经验积累而得到改进的生产产出的特征函数，利用学习曲线可以科学地制定成本计划，改善作业计划、劳动定额与劳力规划，质量改善等。对国际上的研究文献、学习曲线的表现形式及其特点进行分析，探讨了几个新的应用动向。

关键词： 学习曲线     运作管理     行为研究    

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Research on physical shape preserving curve reconstruction

TANG Kelun, ZHANG Xiangwei, CHENG Siyuan, XIONG Hanwei, ZHANG Hong

《机械工程前沿（英文）》 2007年 第2卷 第3期   页码 305-309 doi: 10.1007/s11465-007-0054-2

摘要： Fusion of various data is an effective way to improve the precision and efficiency of acquiring information in reverse engineering. A method of physical shape preserving curve reconstruction is proposed to better realize the data fusion of coordinate measuring machine (CMM) and visual information. From the principle of materials mechanics, the strain energy of the curve corresponding to the distortion is advanced as the internal energy, and the elastic potential energy of the curve is established, using a few precise measured data points as the equilibrium position, to be the external energy. On the basis of the principle of variation calculus, the basic spline finite element method (B-spline FEM) is used to determine the equilibrium position of curve deformation. Numerical simulation indicates that there is an extremely good agreement between the new fitted curve and the actual curve.

关键词： information     CMM     Numerical simulation     effective     coordinate measuring    

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Interpolation of a spline developable surface between a curve and two rulings

Alicia CANTÓN,Leonardo FERNÁNDEZ-JAMBRINA

《信息与电子工程前沿（英文）》 2015年 第16卷 第3期   页码 173-190 doi: 10.1631/FITEE.14a0210

摘要： In this paper we address the problem of interpolating a spline developable patch bounded by a given spline curve and the first and the last rulings of the developable surface. To complete the boundary of the patch, a second spline curve is to be given. Up to now this interpolation problem could be solved, but without the possibility of choosing both endpoints for the rulings. We circumvent such difficulty by resorting to degree elevation of the developable surface. This is useful for solving not only this problem, but also other problems dealing with triangular developable patches.

关键词： Developable surfaces     Spline surfaces     Blossoms    

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Cadmium tolerance and accumulation in fifteen wetland plant species from cadmium-polluted water in constructed

Jianguo LIU,Wen ZHANG,Peng QU,Mingxin WANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 262-269 doi: 10.1007/s11783-014-0746-x

摘要： Variations in cadmium (Cd) tolerances and accumulations among fifteen wetland plant species in moderately (0.5 mg·L ) and heavily (1.0 mg·L ) Cd-polluted wastewaters were investigated in constructed wetlands. Cd removal efficiencies from the wastewaters were more than 90%, and 23.5% and 16.8% of the Cd in the water accumulated in wetland plants for 0.5 and 1.0 mg·L Cd treatments, respectively. The variations among the plant species were 29.4-fold to 48.7-fold in plant biomasses, 5.4-fold to 21.9-fold in Cd concentrations, and 13.8-fold to 29.6-fold in Cd accumulations. The plant species were also largely diversified in terms of Cd tolerance. Some species were tolerant of heavy Cd stress, and some others were sensitive to moderate Cd level. Four wetland plant species were selected for the treatment of Cd-polluted wastewater for their high Cd accumulating abilities and relative Cd tolerances. Plant Cd quantity accumulations are correlated positively and significantly ( <0.05) with plant biomasses and correlated positively but insignificantly ( >0.05) with plant Cd concentrations. The results indicate that the Cd accumulation abilities of wetland plant species are determined mainly by their biomasses and Cd tolerances in growth, which should be the first criteria in selecting wetland plant species for the treating Cd-polluted wastewaters. Cd concentration in the plants may be the second consideration.

关键词： cadmium (Cd)     wastewater treatment     wetland plant     selection     index    

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标题 作者 时间 类型 操作

Meter-scale variation within a single transect demands attention to taxon accumulation curves in riverine

期刊论文

Erratum to: Meter-scale variation within a single transect demands attention to taxon accumulation curves

期刊论文

Is there an inverted U-shaped curve?Empirical analysis of the Environmental Kuznets Curve in agrochemicals

Fei LI,Suocheng DONG,Fujia LI,Libiao YANG

期刊论文

Genotype variations in accumulation of cadmium and lead in celery (

Kun ZHANG, Jianbing WANG, Zhongyi YANG, Guorong XIN, Jiangang YUAN, Junliang XIN, Charlie HUANG

期刊论文

Learning curve of totally thoracoscopic pulmonary segmentectomy

Weibing Wu, Jing Xu, Wei Wen, Yue Yu, Xinfeng Xu, Quan Zhu, Liang Chen

期刊论文

Comparison of growth and lipid accumulation properties of two oleaginous microalgae under different nutrient

Qiao ZHANG,Yu HONG

期刊论文

Experimental study of nitrite accumulation in pre-denitrification biological nitrogen removal process

WU Xuelei, CHEN Lunqiang, PENG Yongzhen, WANG Pu, WANG Yayi

期刊论文

Numerical investigation of circle defining curve for two-dimensional problem with general boundaries

Chung Nguyen VAN

期刊论文

Simultaneous denitrifying phosphorus accumulation in a sequencing batch reactor

YUAN Linjiang, HAN Wei, WANG Lei, YANG Yongzhe, WANG Zhiying

期刊论文

Comparisons in subcellular and biochemical behaviors of cadmium between low-Cd and high-Cd accumulation

Meng XUE, Yihui ZHOU, Zhongyi YANG, Biyun LIN, Jiangang YUAN, Shanshan WU

期刊论文

Heavy metal accumulation and phytostabilization potential of dominant plant species growing on manganese

YANG Shengxiang,LIANG Shichu,YI Langbo,XU Bibo,CAO Jianbing,GUO Yifeng,ZHOU Yu

期刊论文

学习曲线及在工业生产运作研究中的应用综述

陈志祥

期刊论文

Research on physical shape preserving curve reconstruction

TANG Kelun, ZHANG Xiangwei, CHENG Siyuan, XIONG Hanwei, ZHANG Hong

期刊论文

Interpolation of a spline developable surface between a curve and two rulings

Alicia CANTÓN,Leonardo FERNÁNDEZ-JAMBRINA

期刊论文

Cadmium tolerance and accumulation in fifteen wetland plant species from cadmium-polluted water in constructed

Jianguo LIU,Wen ZHANG,Peng QU,Mingxin WANG

期刊论文