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Enrichment and transfer of polycyclic aromatic hydrocarbons (PAHs) through dust aerosol generation from

《环境科学与工程前沿（英文）》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1610-7

摘要：

● Compositional patterns of PAHs in dust aerosol vary from soil during dust generation.

关键词： Dust aerosols     Enrichment factors (EFs)     Polycyclic aromatic hydrocarbons (PAHs)    

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页岩气主要富集因素与核心区选择及评价

王社教,杨涛,张国生,李登华,陈晓明

《中国工程科学》 2012年 第14卷 第6期   页码 94-100

摘要：

影响页岩气规模开发的因素很多，最核心的因素是首先要通过建立地质评价标准，选出页岩气核心区。核心区的确定关系到在页岩气勘探初期，是否能找准页岩气最富集的目标，选择最有利地区进行勘探，突破出气关，进而实现大规模经济开发。从页岩气成藏特征、页岩气富集因素分析入手，重点探讨我国富有机质页岩的丰度、成熟度、脆性矿物含量、含气性以及盖层等关键参数及其作用。借鉴北美页岩气勘探开发和研究成果，结合我国页岩气勘探开发和研究新进展，初步建立我国页岩气核心区地质评价标准，并优选出我国南方海相页岩气的核心区，指出四川盆地南部是我国最现实的页岩气开发区。

关键词： 核心区     选区与评价     富集因素     海相页岩     页岩气    

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Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.007

摘要： The Water Diversion Project from the Yangtze River to Taihu Lake (WDYT) has been widely recognized as an urgent and effective engineering measure to increase water resources, ameliorate the hydrodynamics and water quality conditions, and safeguard the water supply of Taihu Basin. However, some previous studies claimed that WDYT has brought in allochthonous nutrients and should take responsibility for the dramatic increase in phosphorus loading of Taihu Lake in recent years, because Yangtze River has a higher average phosphorus concentration than Taihu Lake. To ensure correct public understanding and provide a critical response to the misconception about the source of phosphorus loading, we quantified contribution of water diversion from the Yangtze River to phosphorus loadings of Taihu Lake over the past twenty years. We reveal that WDYT only diverted 4.3% annually of total phosphorus input of Taihu Lake in the last decade and should not be responsible for the increase in phosphorus concentration and loading in Taihu Lake. We conclude that phosphorus input from the Huxi Region contribute 78% of phosphorus input of Taihu Lake and should be primarily responsible for the high phosphorus concentration of Taihu Lake. Our findings have provided constructive guidance for water resource management of Taihu Basin and phosphorus load control of the second stage of WDYT.
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Experimental investigation on possibility of oxygen enrichment by using gradient magnetic fields

CAI Jun, WANG Li, TONG Lige, SUN Shufeng, WU Ping

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 271-276 doi: 10.1007/s11705-007-0049-x

摘要： This paper presents a novel method that uses the interception effect of gradient magnetic field on oxygen molecules to realize enrichment. The use of two opposite magnetic poles of two magnets at a certain distance forms a magnetic space having a field intensity gradient near its borders. When air injected into the magnetic space outflows from the magnetic space via its borders, oxygen molecules in the air will experience the interception effect of the gradient magnetic field, but nitrogen molecules will outflow from the magnetic space without hindrance. Thus, continuous oxygen enrichment is realized. The enrichment degree of oxygen reaches 0.65% when the inlet and outlet air flows are 40 mL/min and 20 mL/min, respectively, and the gas temperature is 298 K and the maximal product of magnetic flux density and its gradient is 563 T/m (the distance between two magnetic poles is 1 mm). When the gas temperature rises to 343 K, the enrichment degree drops to 0.32%; and when the maximal product of magnetic flux density and field intensity gradient drops to 101 T/m (the distance between two magnetic poles is 4 mm), the enrichment degree drops to 0.23%. The experimental results show that there is an optimal ratio between the inlet air flow and the outlet air flow. Under the experimental conditions in this paper, the value is about 2.0. It is demonstrated that the method presented in this paper can continuously enrich oxygen and has a higher enrichment degree than other oxygen-enrichment methods using magnetic separation.
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the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading enrichment

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

《环境科学与工程前沿（英文）》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1135-2

摘要：

Effect of nitrogen on mixed culture PHA production was reconsidered.

Enrichment history of PHA accumulating culture was discussed.

Higher PHA content and biomass growth were achieved in presence of nitrogen.

Enrichment strategy toward higher PHA accumulation was investigated.

Microbial community succession in PHA accumulation phase was investigated.

关键词： Polyhydroxyalkanoate (PHA)     Organic loading rate     Nitrogen content     Biomass growth     Enrichment history    

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Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0892-z

摘要： Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated. Elevated soil mercury content had significant impact on mercury accumulation in rape stems, roots, seeds and seed coats. Leaf mercury in the leaves was mostly affected by atmospheric input while the stems were mostly affected by soil concentrations. Mercury in the aboveground plant tissue mainly derived from atmospheric absorption, and atmospheric mercury absorption in leaves was higher than that in the stems. Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated using an open top chamber fumigation experiment and a soil mercury enriched cultivation experiment. Results indicate that the mercury concentration in leaves and stems showed a significant variation under different concentrations of mercury in atmospheric and soil experiments while the concentration of mercury in roots, seeds and seed coats showed no significant variation under different atmospheric mercury concentrations. Using the function relation established by the experiment, results for atmospheric mercury sources in rape field biomass showed that atmospheric sources accounted for at least 81.81% of mercury in rape leaves and 32.29% of mercury in the stems. Therefore, mercury in the aboveground biomass predominantly derives from the absorption of atmospheric mercury.

关键词： Open top chamber     Gaseous elemental mercury (GEM)     Soil Mercury     Brassica napus    

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Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 452-458 doi: 10.1007/s11684-009-0080-z

摘要： The authors performed a meta-analysis of case-control studies that addressed whether reproductive factors and oral contraceptive use were associated with breast cancer by searching the MEDLINE, PubMed, Proquest, Embase, ScienceDirect, African Healthline, BMJ Health Intelligence and Chinese Periodical net databases for all English-language and Chinese-language papers published from January 1, 1997 to December 31, 2007. A total of 15 studies calculating pool ORs indicated that menopausal age >50yr [odds ratio (OR), 1.39; 95% confidence interval (CI), 1.22―1.57] and oral contraceptive use (OR, 2.12*, “*”: summary OR was adjusted; 95% CI, 1.24―3.62) were correlated with the increase in breast cancer risk while the summary OR based on number of full-term pregnancies ≥1 (OR, 0.63*; 95% CI, 0.60―0.68) and breast-feeding (OR, 0.76; 95% CI, 0.64―0.90) indicated no association with breast cancer risk. The correlation was statistically significant. Menopausal age >50yr and oral contraceptive use are positively correlated with an increase in breast cancer risk while breast-feeding and number of full-term pregnancies ≥1 are protective factors.

关键词： meta-analysis     breast cancer     risk factors     reproductive factors     oral contraceptive use    

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Risk factors of prognosis after acute kidney injury in hospitalized patients

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 393-402 doi: 10.1007/s11684-017-0532-9

摘要：

The risk factors, especially laboratory indicators, of prognosis after acute kidney injury (AKI) remain unclear. We conducted a retrospective survey of Chinese People’s Liberation Army General Hospital from January 1, 2012 to December 31, 2012 according to the AKI diagnosis standard issued by Kidney Disease Improving Global Outcomes. The epidemiological features and factors influencing hospital mortality and renal function recovery were evaluated through logistic regression analysis. Among 77 662 cases of hospitalized patients, 1387 suffered from AKI. The incidence rate and mortality of AKI were 1.79% and 14.56%, respectively. Multivariate logistic regression analysis revealed that high AKI stage, age greater than 80 years, neoplastic disease, low cardiac output, increased white blood cell count, and decreased platelet count and serum albumin levels were the risk factors affecting the mortality of AKI patients. Conversely, body mass index between 28 and 34.9 was a protective factor. Increased AKI stage, tumor disease, post-cardiopulmonary resuscitation, and RRT were the risk factors of renal function recovery upon discharge. In addition to traditional risk factors, white blood cell count, platelet count, albumin, and BMI were the predictors of the mortality of AKI patients. No laboratory indicators were found to be the risk factors of renal function recovery in AKI patients.

关键词： acute kidney injury     risk factors     prognosis    

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Effective enrichment of Zn from smelting wastewater via an integrated Fe coagulation and hematite precipitation

Zhan Qu, Ting Su, Yu Chen, Xue Lin, Yang Yu, Suiyi Zhu, Xinfeng Xie, Mingxin Huo

《环境科学与工程前沿（英文）》 2019年 第13卷 第6期 doi: 10.1007/s11783-019-1178-4

摘要： 98.5% Zn was enriched from Zn-bearing smelting wastewater. 99.5% Fe was hydrothermally precipitated into hematite nanoparticles. Highly purified hematite nanoparticles were obtained. The residual Zn was 2169 mg/L, 290 times of that in smelting wastewater. Coagulation is commonly applied to treat Zn-bearing wastewater from smelting industries (smelting wastewater), and thus the Zn-bearing sludge was considerably produced, which should be solidified before safety disposal. Herein, we demonstrated a novel approach to recycle Zn effectively from smelting wastewater via an integrated Fe coagulation and hematite precipitation method. First, smelting wastewater was coagulated by adding ferric chloride to generate Fe/Zn-bearing sludge (sludge for short). Secondly, the sludge was dissolved to generate an acid solution containing 2.2 g/L of Zn and 39.2 g/L of Fe. Thirdly, the Fe/Zn-bearing solution was hydrothermally treated, and 89% of Fe was eliminated to highly purified hematite block, whereas the percentage of Zn lost was below 1.1%. Finally, the hematite precipitates were collected, and the supernatant was hydrothermally treated again with the addition of glucose. When the molar ratio of glucose to Fe in the supernatant was 1.5, over 99.5% of Fe was precipitated in hematite nanoparticles with a diameter of 10–100 nm, and the residual Fe was 21.5 mg/L. The loss of Zn was below 0.4%, and the residual Zn in the solution was 2169 mg/L, 290 times of that in the smelting wastewater. The major mechanism for Fe removal was the hydrolysis of ferric nitrate into hematite, which was promoted by nitrate consumption in glucose oxidation. This paper is the first report of an environment-friendly method for enriching Zn without generating any waste.

关键词： Smelting wastewater     Hydrothermal     Hematite precipitation     Heavy metals    

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Factors affecting the distribution of microplastics in soils of China

《环境科学与工程前沿（英文）》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1710-4

摘要：

● Microplastic (MP) abundance in soil of China was highly heterogeneous.

关键词： Microplastic distribution     Microplastic heterogeneity     Effecting factors     Agriculture     Socio-economic factors    

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Epidemic obesity in children and adolescents: risk factors and prevention

Eun Young Lee, Kun-Ho Yoon

《医学前沿（英文）》 2018年 第12卷 第6期   页码 658-666 doi: 10.1007/s11684-018-0640-1

摘要： The prevalence of obesity among children and adolescents (aged 2–18 years) has increased rapidly, with more than 100 million affected in 2015. Moreover, the epidemic of obesity in this population has been an important public health problem in developed and developing countries for the following reasons. Childhood and adolescent obesity tracks adulthood obesity and has been implicated in many chronic diseases, including type 2 diabetes, hypertension, and cardiovascular disease. Furthermore, childhood and adolescent obesity is linked to adulthood mortality and premature death. Although an imbalance between caloric intake and physical activity is a principal cause of childhood and adolescent obesity, environmental factors are exclusively important for development of obesity among children and adolescents. In addition to genetic and biological factors, socioenvironmental factors, including family, school, community, and national policies, can play a crucial role. The complexity of risk factors for developing obesity among children and adolescents leads to difficulty in treatment for this population. Many interventional trials for childhood and adolescent obesity have been proven ineffective. Therefore, early identification and prevention is the key to control the global epidemic of obesity. Given that the proportion of overweight children and adolescents is far greater than that of obesity, an effective prevention strategy is to focus on overweight youth, who are at high risk for developing obesity. Multifaceted, comprehensive strategies involving behavioral, psychological, and environmental risk factors must also be developed to prevent obesity among children and adolescents.

关键词： obesity     children     adolescents     epidemiology     risk factor     prevention    

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CRITICAL PROCESSES AND MAJOR FACTORS THAT DRIVE NITROGEN TRANSPORT FROM FARMLAND TO SURFACE WATER BODIES

《农业科学与工程前沿（英文）》 2023年 第10卷 第4期   页码 541-552 doi: 10.15302/J-FASE-2023518

摘要：

Agricultural non-point source pollution is increasingly an important issue affecting surface water quality. Currently, the majority of the studies on nitrogen loss have focused on the agricultural field scale, however, the response of surface water quality at the watershed scale into the nitrogen loss at the field scale is poorly understood. The present study systematically reviewed the critical processes and major factors that nitrogen transport from farm fields to surface water bodies. The critical processes of farmland nitrogen entering surface water bodies involve the processes of nitrogen transport from farmland to ditches and the transformation processes of nitrogen during migration in ditches/rivers. Nitrogen transport from farmland to ditches is one of the prerequisites and critical processes for farmland nitrogen transport to surface water bodies. The transformation of nitrogen forms in ditches/rivers is an intermediate process in the migration of nitrogen from farmland to surface water bodies. Nitrogen loss from farmland is related to soil storage and exogenous inputs. Therefore, nitrogen input management should not only consider the current input, but also the contribution of soil storage due to the historical surpluses. Ditches/rivers have a strong retention capacity for nitrogen, which will significantly affect the process of farmland nitrogen entering surface water bodies. The factors affecting nitrogen transformation in river/ditches can be placed in four categories: (1) factors affecting hydraulic retention time, (2) factors affecting contact area, (3) factors affecting biological activity, and (4) forms and amount of nitrogen loading to river/ditches. Ditch systems are more biologically (including plants and microbes) active than rivers with biological factors having a greater influence on nitrogen transformation. When developing pollution prevention and control strategies, ecological ditches can be constructed to increase biological activity and reduce the amount of surplus nitrogen entering the water body. The present research should be valuable for the evaluation of environment impacts of nitrogen loss and the non-point source pollution control.

关键词： nitrogen     loss from soil     transformation     farm field scale     watershed scale    

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Oocyte-associated transcription factors in reprogramming after somatic cell nuclear transfer: a review

Fengxia YIN,Hui LIU,Shorgan BOU,Guangpeng LI

《农业科学与工程前沿（英文）》 2014年 第1卷 第2期   页码 104-113 doi: 10.15302/J-FASE-2014003

摘要： Oocytes are unique cells with the inherent capability to reprogram nuclei. The reprogramming of the somatic nucleus from its original cellular state to a totipotent state is essential for term development after somatic cell nuclear transfer. The nuclear-associated factors contained within oocytes are critical for normal fertilization by sperm or for somatic cell nuclear reprogramming. The chromatin of somatic nuclei can be reprogrammed by factors in the egg cytoplasm whose natural function is to reprogram sperm chromatin. The oocyte first obtains its reprogramming capability in the early fetal follicle, and then its capacity is enriched in the late growth phase and reaches its highest capability for reprogramming as fully-grown germinal vesicle oocytes. The cytoplasmic milieu most likely contains all of the specific transcription and/or reprogramming factors necessary for cellular reprogramming. Certain transcription factors in the cytoplast may be critical as has been demonstrated for induced pluripotent stem cells. The maternal pronucleus exerts a predominant, transcription-dependent effect on embryo cytofragmentation, with a lesser effect imposed by the ooplasm and the paternal pronucleus. With deep analysis of transcriptomics in oocytes and early developmental stage embryos more maternal transcription factors inducing cellular reprogramming will be identified.

关键词： nuclear reprogramming     somatic cell     transcription factors     transcriptomics    

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Understanding coupled factors that affect the modelling accuracy of typical planar compliant mechanisms

Guangbo HAO,Haiyang LI,Suzen KEMALCAN,Guimin CHEN,Jingjun YU

《机械工程前沿（英文）》 2016年 第11卷 第2期   页码 129-134 doi: 10.1007/s11465-016-0392-z

摘要：

In order to accurately model compliant mechanism utilizing plate flexures, qualitative planar stress (Young’s modulus) and planar strain (plate modulus) assumptions are not feasible. This paper investigates a quantitative equivalent modulus using nonlinear finite element analysis (FEA) to reflect coupled factors in affecting the modelling accuracy of two typical distributed-compliance mechanisms. It has been shown that all parameters have influences on the equivalent modulus with different degrees; that the presence of large load-stiffening effect makes the equivalent modulus significantly deviate from the planar assumptions in two ideal scenarios; and that a plate modulus assumption is more reasonable for a very large out-of-plane thickness if the beam length is large.

关键词： coupling factors     modelling accuracy     compliant mechanisms     equivalent modulus    

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标题 作者 时间 类型 操作

Enrichment and transfer of polycyclic aromatic hydrocarbons (PAHs) through dust aerosol generation from

期刊论文

Distribution, enrichment mechanism and risk assessment for fluoride in groundwater: a case study of Mihe-Weihe

期刊论文

页岩气主要富集因素与核心区选择及评价

王社教,杨涛,张国生,李登华,陈晓明

期刊论文

Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

期刊论文

Experimental investigation on possibility of oxygen enrichment by using gradient magnetic fields

CAI Jun, WANG Li, TONG Lige, SUN Shufeng, WU Ping

期刊论文

the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading enrichment

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

期刊论文

Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

期刊论文

Meta-analysis of the risk factors of breast cancer concerning reproductive factors and oral contraceptive

Qiong DAI MD, Bei LIU MD, Yukai DU MM,

期刊论文

Risk factors of prognosis after acute kidney injury in hospitalized patients

null

期刊论文

Effective enrichment of Zn from smelting wastewater via an integrated Fe coagulation and hematite precipitation

Zhan Qu, Ting Su, Yu Chen, Xue Lin, Yang Yu, Suiyi Zhu, Xinfeng Xie, Mingxin Huo

期刊论文

Factors affecting the distribution of microplastics in soils of China

期刊论文

Epidemic obesity in children and adolescents: risk factors and prevention

Eun Young Lee, Kun-Ho Yoon

期刊论文

CRITICAL PROCESSES AND MAJOR FACTORS THAT DRIVE NITROGEN TRANSPORT FROM FARMLAND TO SURFACE WATER BODIES

期刊论文

Oocyte-associated transcription factors in reprogramming after somatic cell nuclear transfer: a review

Fengxia YIN,Hui LIU,Shorgan BOU,Guangpeng LI

期刊论文

Understanding coupled factors that affect the modelling accuracy of typical planar compliant mechanisms

Guangbo HAO,Haiyang LI,Suzen KEMALCAN,Guimin CHEN,Jingjun YU

期刊论文