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Decontamination efficiency and root structure change in the plant-intercropping model in vertical-flow

Yonghua CHEN, Xiaofu WU, Mingli CHEN, Kelin LI, Jing PENG, Peng ZHAN

《环境科学与工程前沿（英文）》 2013年第7卷第6期页码 906-912 doi: 10.1007/s11783-013-0579-z

摘要： Subtropical climatic conditions can contribute to the death of the aerial parts of constructed wetland plants in winter. This presents a barrier to the widespread application of constructed wetland and is an issue that urgently needs to be solved. Three contrasting experiments, the plant-intercropping model (A), the warm-seasonal plant model (B), and the non-plant model (C), were studied in terms of their efficiency in removing pollutants, and the change in root structure of plants in the plant-intercropping model within the vertical-flow constructed wetlands. The results indicate that model A was able to solve the aforementioned problem. Overall, average removal rates of three pollutants (COD , total nitrogen (TN) and total phosphorous (TP)) using model A were significantly higher than those obtained using models B and C ( <0.01). Moreover, no significant differences in removal rates of the three pollutants were detected between A and B during the higher temperature part of the year ( >0.05). Conversely, removal rates of the three pollutants were found to be significantly higher using model A than those observed using model B during the lower temperature part of the year ( <0.01). Furthermore, the morphologies and internal structures of plant roots further demonstrate that numerous white roots, whose distribution in soil was generally shallow, extend further under model A. The roots of these aquatic plants have an aerenchyma structure composed of parenchyma cells, therefore, roots of the cold-seasonal plants with major growth advantages used in A were capable of creating a more favorable vertical-flow constructed wetlands media-microenvironment. In conclusion, the plant-intercropping model (A) is more suitable for use in the cold environment experienced by constructed wetland during winter.

关键词： vertical-flow constructed wetlands plant intercropping model warm seasonal plant model

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Numerical simulation of underground seasonal cold energy storage for a 10 MW solar thermal power plant

Zulkarnain ABBAS, Yong LI, Ruzhu WANG

《能源前沿（英文）》 2021年第15卷第2期页码 328-344 doi: 10.1007/s11708-020-0676-1

摘要： This paper aims to explore an efficient, cost-effective, and water-saving seasonal cold energy storage technique based on borehole heat exchangers to cool the condenser water in a 10 MW solar thermal power plant. The proposed seasonal cooling mechanism is designed for the areas under typical weather conditions to utilize the low ambient temperature during the winter season and to store cold energy. The main objective of this paper is to utilize the storage unit in the peak summer months to cool the condenser water and to replace the dry cooling system. Using the simulation platform transient system simulation program (TRNSYS), the borehole thermal energy storage (BTES) system model has been developed and the dynamic capacity of the system in the charging and discharging mode of cold energy for one-year operation is studied. The typical meteorological year (TMY) data of Dunhuang, Gansu province, in north-western China, is utilized to determine the lowest ambient temperature and operation time of the system to store cold energy. The proposed seasonal cooling system is capable of enhancing the efficiency of a solar thermal power plant up to 1.54% and 2.74% in comparison with the water-cooled condenser system and air-cooled condenser system respectively. The techno-economic assessment of the proposed technique also supports its integration with the condenser unit in the solar thermal power plant. This technique has also a great potential to save the water in desert areas.

关键词： seasonal cold energy storage borehole heat exchangers typical meteorological data TRNSYS condenser cooling techno-economic assessment

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Spectral characteristics of plant communities from salt marshes: A case study from Chongming Dongtan,

ZHANG Liquan, GAO Zhanguo, Armitage Richard, Kent Martin

《环境科学与工程前沿（英文）》 2008年第2卷第2期页码 187-197 doi: 10.1007/s11783-008-0004-1

摘要： The spectral reflectance of recently formed salt marshes at the mouth of the Yangtze River, which are undergoing invasion by , were assessed to determine the potential utility of remotely sensed data in assessing future invasion and changes in species composition. Following a review of published research on remote sensing of salt marshes, 53 locations along three transects were sampled for paired data on plant species composition and spectral reflectance using a FieldSpec Pro JR Field Portable Spectroradiometer. Spectral data were processed concerning reflectance, and the averaged reflectance values for each sample were re-analysed to correspond to a 12-waveband bandset of the Compact Airborne Spectral Imager. The spectral data were summarised using principal components analysis (PCA) and the relationships between the vegetation composition, and the PCA axes of spectral data were examined. The first PCA axis of the reflectance data showed a strong correlation with variability in near infrared reflectance and ‘brightness’, while the second axis was correlated with visible reflectance and ‘greenness’. Total vegetation cover, vegetation height, and mudflat cover were all significantly related to the first axis. The implications of this in terms of the ability of remote sensing to distinguish the various salt marsh species and in particular the invasive species were discussed. Major differences in species with various physiognomies could be recognised but problems occurred in separating early colonising from other species at that stage. Further work using multi-seasonal hyperspectral data might assist in solving these problems.

关键词： Spectral multi-seasonal hyperspectral invasive JR re-analysed

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Optimization for operating modes based on simulation of seasonal underground thermal energy storage

ZHAO Jun, CHEN Yan, LI Xinguo

《能源前沿（英文）》 2008年第2卷第3期页码 298-301 doi: 10.1007/s11708-008-0053-y

摘要： A simulation was performed, which concerned the feasibility of seasonal underground thermal energy storage (UTES) in Tianjin, China. The investigated system consisted of 8 boreholes. In summer, residual solar thermal energy was emitted into the soil surrounding the borehole heat exchangers through which the stored energy was extracted in winter with a ground coupled heat pump (GCHP) to provide a proper heating temperature. A simulation study was performed to study the influence of system operation modes on thermal recovery based on the experimental data of a GCHP system, local meteorological conditions and soil properties in Tianjin. The results indicate a thermal recovery ratio of less than 67% and different temperature distributions under three modes. Finally, an operation mode was suggested based on both lower loss and better thermal recovery in the UTES.

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Full-scale site evaluation of ventilation expressway embankments underlain by warm permafrost along the

《结构与土木工程前沿（英文）》页码 1047-1059 doi: 10.1007/s11709-023-0034-6

摘要： Ventilation embankments, including those with forced ventilation, natural ventilation, and combination of these, were adopted for the construction of the Gonghe−Yushu Expressway in warm permafrost areas. To evaluate the actual thermal performance of ventilation embankment in the Qinghai−Tibet Plateau, four types of ventilation embankments were selected as objects, and their long-term thermal characteristics were analyzed based on monitoring data. It was found that: 1) under the strong scale effect of a wide embankment, the crushed-rock embankment (CRE) was warming up and the permafrost table was declining year by year. Meanwhile, the combined ventilated slab and CRE and ventilated ducts embankment can effectively decrease the ground temperature and raise permafrost table in the year with a colder winter; 2) transverse temperature difference caused by the shady–sunny slope effect existed in all the four embankments. However, it was weakened by the combined ventilated slab and CRE and the ventilated ducts embankment due to their stronger cooling effect; and 3) the pre-existing embankment had a remarkable thermal disturbance to the adjacent newly-built embankment, so a reasonable embankment spacing should be considered in practical engineering. These findings would provide a reference for construction of expressway embankments in permafrost regions.

关键词： warm permafrost expressway ventilation embankments temperature field

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Seasonal and treatment-process variations in invertebrates in drinking water treatment plants

Zhiling Wu, Xianchun Tang, Hongbin Chen

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1354-6

摘要： Abstract • Seasonal and treatment-process variations in invertebrates in a DWTP were analyzed. • The propagation and leakage of invertebrates in BAC filter were the most serious. • Invertebrates can survive and reproduce in chlorine disinfected clear water tanks. • Proportions of endogenous invertebrates increased along the treatment process. Problems associated with excessive propagation and leakage of invertebrates in drinking water have received increasing attention in recent years. We performed a monthly survey of invertebrate abundance and taxa in the effluent of each treatment stage in a drinking water treatment plant between May 2015 and April 2016 and analyzed seasonal and treatment-process variations in invertebrates. The results showed that invertebrate abundances in raw water, effluent of the biological activated carbon (BAC) filter, and finished water significantly correlated with water temperature, whereas no correlation was observed between water temperature and invertebrate abundance in the effluents of the sedimentation tank and sand filter. The dominant taxa in the effluent of each treatment stage were rotifers, nematodes, and crustaceans. The sedimentation tank could efficiently remove invertebrates with an annual average removal rate of 92%. The propagation and leakage of invertebrates occurred in the sand and BAC filters but more seriously in the latter. The average reproduction rate in the BAC filter was 268.8% with rotifers as the taxon that leaked the most. Invertebrate survival and reproduction were also observed in the chlorine-disinfected clean water reservoir with an average reproduction rate of 41.9%. Owing to differences in chlorine resistance, the reproduction ability of the dominant taxa was in the order nematodes>crustaceans>rotifers. The proportion of endogenous invertebrates gradually increased along the treatment process. The average proportion of endogenous invertebrates in the finished water was higher than 79.0%. Our findings suggested that waterworks should pay more attention to endogenous invertebrate growth.

关键词： Invertebrates Drinking water Seasonal variations Treatment process

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The second short-term warm ischemia after vascular anastomosis did not affect early renal function recovery

null

《医学前沿（英文）》 2012年第6卷第3期页码 329-331 doi: 10.1007/s11684-012-0211-9

摘要：

Ischemic postconditioning was defined as rapid intermittent interruptions of blood ?ow in the early phase of reperfusion, which has been found to be protective against renal ischemia-reperfusion injury (IRI) in animal models but not in clinical trials. We describe a case that the allograft renal vein was twisted because of the surgeon’s mistake, which caused the warm ischemia of allograft after reperfusion. The allograft restored blood flow without second reperfusion and cold preservation after 9 min of warm ischemia. The patient was followed up for 3 months and the allograft worked well without complications.

关键词： renal transplantation vein twist ischemia-reperfusion injury

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Impacts of emissions and meteorological changes on China’s ozone pollution in the warm seasons of 2013

Dian Ding, Jia Xing, Shuxiao Wang, Xing Chang, Jiming Hao

《环境科学与工程前沿（英文）》 2019年第13卷第5期 doi: 10.1007/s11783-019-1160-1

摘要： O3 increment is mainly caused by changes in meteorology rather than emissions. Emission reduction is effective to reduce O3 nationwide, especially in summer. Strengthened NOx controls are necessary to meet the ambient O3 standard. We have quantified the impacts of anthropogenic emissions reductions caused by the Air Pollution Control Action Plan and changes in meteorological fields between 2013 and 2017 on the warm-season O3 concentration in China using a regional 3D chemical transport model. We found that the impact on daily maximum eight-hour (MDA8) O3 concentration by the meteorological variation that mostly increased O3 was greater than that from emission reduction, which decreased O3. Specifically, the control measures implemented since 2013 in China have reduced SO2, NOx, PM2.5, and VOC emissions by 33%, 25%, 30%, and 4% in 2017, while NH3 emissions have increased by 7%. The changes in anthropogenic emissions lowered MDA8 O3 by 0.4–3.7 ppb (0.8%–7.6%, varying by region and month), although MDA8 O3 was increased slightly in some urban areas (i.e. North China) at the beginning/end of warm seasons. Relative to 2013, the average 2 m temperature in 2017 shows increments in North, North-east, East, and South China (0.34℃–0.83℃) and decreases in Central China (0.24℃). The average solar radiation shows increments in North, North-east, and South China (7.0–9.7 w/m2) and decreases in Central, South-west, and North-west China (4.7–10.3 w/m2). The meteorological differences significantly change MDA8 O3 by -3.5–8.5 ppb (-8.2%–18.8%) with large temporal variations. The average MDA8 O3 was slightly increased in North, North-east, East, and South China. The response surface model suggests that the O3 formation regime transfers from NOx-saturated in April to NOx-limited in July on average in China.

关键词： O₃ pollution Meteorological influences Emission reduction NO_x VOC

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Seasonal variation of nitrogen and phosphorus in Xiaojiang River—A tributary of the Three Gorges Reservoir

Zhe LI , Jinsong GUO , Man LONG , Fang FANG , Jinping SHENG , Hong ZHOU ,

《环境科学与工程前沿（英文）》 2009年第3卷第3期页码 334-340 doi: 10.1007/s11783-009-0039-y

摘要： A yearlong monitoring program in the backwater area of Xiaojiang River (XBA) was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir (TGR) in China, starting after the impoundment water level of the TGR reached 156 m. From March 2007 to March 2008, the average concentration of total nitrogen (TN) and total phosphorus (TP) were (1553 ± 484) μg·L and (62 ± 31) μg·L, respectively. The mean value of chlorophyll was (9.07 ± 0.91) μg·L. The trophic level of XBA was meso-eutrophic, while the general nutrient limitation was phosphorus. The results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial runoff. The variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TP<22. N-fixation from cyanobacteria occurred and became an important process in overcoming the nitrogen deficit under a low TN/TP ratio. When TN/TP ≥ 22, the variation of TP affected the TN/TP ratio more significantly than TN. The increase of TP in XBA was caused mainly by particulate phosphorus, which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface runoff. An increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.

关键词： Three Gorges Reservoir eutrophication nitrogen phosphorus seasonal variation chlorophyll

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海洋天然气水合物藏开采若干问题研究

白玉湖,李清平

《中国工程科学》 2011年第13卷第5期页码 103-112

摘要：

文章阐述了在开采天然气水合物方面所取得的研究进展，包括天然气水合物开采模型及数值模拟，天然气水合物开采物理模拟相似准则，天然气水合物开采方法研究等。建立、完善了天然气水合物开采的数学模型，并以此为基础建立了降压开采水合物物理模拟相似准则。降压法开采单一水合物藏，在某些情况下开采能量不足会导致藏内结冰严重。对下伏气的天然气水合物藏而言，水合物能够提高产气量、延长稳产时间。结合降压和注热的优势提出了注温水-降压法联合开采方法，该方法具有稳产时间较长、稳产气速度高的特点。

关键词：天然气水合物降压法注温水-降压联合开采方法数学模型相似准则

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长江上游干暖河谷地区气候和土地利用变化的水文响应 Article

李聪聪, 蔡宴朋, 李中, 张倩倩, 孙炼, 李欣怡, 周硼硝

《工程（英文）》 2022年第19卷第12期页码 24-39 doi: 10.1016/j.eng.2021.04.029

摘要：

中国西南山区干暖河谷的水文过程具有独特的特点，已引起世界科学界的广泛关注。鉴于该地区是长江上游生态系统脆弱和水资源冲突严重的地区，需系统地识别气候和土地利用变化的水文响应。本研究以安宁河流域的干暖河谷为研究对象，采用MIKE SHE模型进行校准。随后，利用长短期记忆网络模型（LSTM）和传统多模式集成均值（MMEM）方法对31个全球气候模式（GCM）进行气候预测。采用元胞自动机-马尔可夫模型，综合考虑气候、社会和经济条件等，对土地利用的空间格局进行预测。将生成的4组气候预测和3组土地利用预测数据交叉输入MIKE SHE模型，以预测2021—2050年的水文响应变化。针对日尺度模拟的率定期和第一个验证期，决定性系数（R）分别为0.85和0.87，纳什效率系数分别为0.72和0.73；先进的LSTM方法对日尺度气温和月尺度降水的预测效果优于传统的MMEM方法；RCP8.5下的月平均气温预测值略高于RCP4.5，这与6~10月月平均降水量的变化相反；径流量和实际蒸散发（ET）的变化对气候变化的敏感性高于对土地利用变化的敏感性；研究区径流量变化与ET变化无显著相关性。本研究可以提供复杂变化环境下的一系列水文响应，从而有助于关键地区水资源随机不确定性和优化管理。

关键词：干暖河谷水文模拟多气候模式集成气候变化土地利用变化

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IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

《农业科学与工程前沿（英文）》 2021年第8卷第4期页码 635-644 doi: 10.15302/J-FASE -2020343

摘要：

The antifungal effectiveness of extracts of five medicinal plant species was determined. The inhibitory activity of extracts of Eucalyptus tereticornis, Xanthium sibiricum, Artemisia argyi, Tupistra chinensis and Pyrola calliantha were evaluated against the mycelial growth of the plant pathogenic fungi Aspergillus niger, Botrytis cinerea, Penicillium digitatum, P. expansum, P. italicumand Rhizopus stolonifer. All plant extracts were prepared at 60°C using solvents (either water, 50% ethanol (v/v), 95% ethanol (v/v), ethyl acetate or petroleum ether). Fungicidal effects of all plants tested were confirmed. Different extracts from the same plant species gave different degrees of inhibition. All aqueous extracts had weak or no activity on all fungi tested. Ethyl acetate and 95% ethanol extracts from T. chinensis rhizomes gave greater inhibition and a broader spectrum inhibition than the other extracts. T. chinensis may have potential as a new natural fungicide and may be used for the preservation of agricultural and forestry products such as fruits and vegetables.

关键词： Botrytis cinerea / food preservation / plant diseases / plant pathogenic fungi / Tupistra chinensis

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Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要： Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

关键词： terminal restriction fragment length polymorphism (T-RFLP) bacterial community structure marine microbial diversity HhaI MspI

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Using balance of seasonal herbage supply and demand to inform sustainable grassland management on the

Xinquan ZHAO, Liang ZHAO, Qi LI, Huai CHEN, Huakun ZHOU, Shixiao XU, Quanmin DONG, Gaolin WU, Yixin HE

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 1-8 doi: 10.15302/J-FASE-2018203

摘要： To mitigate the impacts of grassland degradation on the Qinghai–Tibetan Plateau (QTP), in recent decades China has been implementing large-scale conservation programs and has invested about 42 billion CNY (7 billion USD). However, these programs are faced with major challenges involving trade-offs between ecological function, livestock production and income of pastoralists. Scientific assessments, as well as technical and policy issues, have not fully captured the complex ecological, social and economic dynamics of the challenges facing grassland management on the QTP. Pastoral livestock production on the QTP is characterized by imbalance in both quality and quantity between livestock seasonal nutrient requirements and herbage production, which forces pastoralists to keep larger numbers of livestock for longer periods, leading to overgrazing. To solve these problems, an integrated crop-livestock system is promoted to improve the efficiency of livestock production and conserve natural grassland as well for a sustainable system for the QTP.

关键词： ecosystem function grassland degradation grassland management integrated rangeland-cropland-livestock production system Qinghai–Tibetan Plateau

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An introduction to the medicinal plant genome project

Shilin Chen, Li Xiang, Xu Guo, Qiushi Li

《医学前沿（英文）》 2011年第5卷第2期页码 178-184 doi: 10.1007/s11684-011-0131-0

摘要： In recent years, genomics has developed rapidly with the application of next-generation sequencing technology. However, very few studies have been carried out on genomics for medicinal plants. This paper introduces the genome research of medicinal plants, including genome sequencing, assembly, annotation, and functional genomics, to set up the foundation for the development of natural medicines and the selection of cultivars with good agricultural traits. This study places the study on traditional Chinese medicine into the frontier field of life science.

关键词： genomics medicinal plant sequencing application

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标题作者时间类型操作

Decontamination efficiency and root structure change in the plant-intercropping model in vertical-flow

Yonghua CHEN, Xiaofu WU, Mingli CHEN, Kelin LI, Jing PENG, Peng ZHAN

期刊论文

Numerical simulation of underground seasonal cold energy storage for a 10 MW solar thermal power plant

Zulkarnain ABBAS, Yong LI, Ruzhu WANG

期刊论文

Spectral characteristics of plant communities from salt marshes: A case study from Chongming Dongtan,

ZHANG Liquan, GAO Zhanguo, Armitage Richard, Kent Martin

期刊论文

Optimization for operating modes based on simulation of seasonal underground thermal energy storage

ZHAO Jun, CHEN Yan, LI Xinguo

期刊论文

Full-scale site evaluation of ventilation expressway embankments underlain by warm permafrost along the

期刊论文

Seasonal and treatment-process variations in invertebrates in drinking water treatment plants

Zhiling Wu, Xianchun Tang, Hongbin Chen

期刊论文

The second short-term warm ischemia after vascular anastomosis did not affect early renal function recovery

null

期刊论文

Impacts of emissions and meteorological changes on China’s ozone pollution in the warm seasons of 2013

Dian Ding, Jia Xing, Shuxiao Wang, Xing Chang, Jiming Hao

期刊论文

Seasonal variation of nitrogen and phosphorus in Xiaojiang River—A tributary of the Three Gorges Reservoir

Zhe LI , Jinsong GUO , Man LONG , Fang FANG , Jinping SHENG , Hong ZHOU ,

期刊论文

海洋天然气水合物藏开采若干问题研究

白玉湖,李清平

期刊论文

长江上游干暖河谷地区气候和土地利用变化的水文响应

李聪聪, 蔡宴朋, 李中, 张倩倩, 孙炼, 李欣怡, 周硼硝

期刊论文

IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

期刊论文

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

期刊论文

Using balance of seasonal herbage supply and demand to inform sustainable grassland management on the

Xinquan ZHAO, Liang ZHAO, Qi LI, Huai CHEN, Huakun ZHOU, Shixiao XU, Quanmin DONG, Gaolin WU, Yixin HE

期刊论文

An introduction to the medicinal plant genome project

Shilin Chen, Li Xiang, Xu Guo, Qiushi Li

期刊论文

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