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EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

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Journal of Environmental Sciences 2007年第12期19卷 1496-1499页

作者： WANG Hong-qi LU Si-jin LI hua YAO Zhi-hua College of Water Sciences Beijing Normal University Beijing 100875 China.

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils. Bidens is a new Pb hyperaccumulator, which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb. The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues. The Pb distribution order in the B. was： leaf 〉 stem 〉 root. The effect of amendments on phytoremediation was also studied. The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application. Compared with CK （control check）, EDTA application promoted translocation of Pb to overground parts of the plant. The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg. This research demonstrated that B. maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil, especially, combination with EDTA.

关键词： phytoremediation Bidens maximowicziana lead amendment EDTA

China's First Independent Cobalt Deposit and its Metallogenic Mechanism:Evidence from Fluid Inclusions and Isotopic Geochemistry

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1403-1418页

作者： FENG Chengyou qi Feng ZHANG Dequan LI Daxin SHE Hongquan School of Earth and Space Sciences Peking University Beijing 1008 71 China Key Laboratory of Metallogeny and Mineral Resource Assessment Ministry of Land and Resources＂ Institute of Mineral Resources CA GS Beijing 100037 China

The Tuolugou cobalt deposit is the first independent large-scale Co- and Au-bearing deposit discovered in northwestern China. It is located in the eastern Kunlun orogenic belt in qinghai Province, and occurs conformably in low-grade metamorphic volcano-sedimentary rock series with well-developed Na-rich hydrothermal sedimentary rocks and typical hydrothermal sedimentary ore fabrics. Fluid inclusions and isotopic geochemistry studies suggest that cobalt mineralizing fluid is dominated by NaCI-H20 system, accompanied by NaCI-CO2-H20-N2 system responsible for gold mineralization. Massive, banded and disseminated pyrite ores have similar compositions of He and Ar isotopes from the mineralizing fluid, with 3He/4He range between 0.10 to 0.31Ra （averaging 0.21Ra）, and 4~Ar/36Ar between 302 and 569 （averaging 373）, which reflects that Co mineralizing fluids derived dominantly from meteoric water deeply circulating. ~34S values of pyrite approaches to zero （~34S ranging from -4.5%o to ＋1.5%o, centering around -1.8%o to -0.2%o）, reflecting its deep source. Ore lead is characterized by distinctly high radiogenesis, with 2~6pb/2~4pb〉19.279, 2~7pb/2~4pb〉15.691 and 2~spb/2~4pb〉39.627, and its values show an increase trend from country rocks, regional Paleozoic volcanic rocks to ores. This may have suggested that high radiogentic ore Pb derived mainly from country rocks by leaching meteoric water-dominated hydrothermal fluid during its circulation at depth. Cobalt occurs mainly in sulfide phase （such as pyrite）, but cobalt enrichment, and presence and increasing contents of Co-bearing minerals have a positive correlation with metamorphic degree. The Tuolugou deposit and other typical strata-bound Co-Cu-Au deposits have striking similarities in the geological features and metallogenic pattern of primary cobalt. All of them are syngenetic hydrothermal exhalative sedimentation in origin.

关键词： cobalt deposit fluid inclusion isotopic geochemistry SEDEX metallogenic mechanism Tuolugou in qinghai Province eastern Knnlun orogenic belt

Experimental Investigation on Performance of Pulse Detonation Rocket Engine Model

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Chinese Journal of Aeronautics 2007年第1期20卷 9-14页

作者： LI qiang FAN Wei YAN Chuan-jun HU Cheng-qi YE Bin School of Engine and Energy Northwestern Polytechnical University Xi＇an 710072 China

The PDRE test model used in these experiments utilized kerosene as the fuel, oxygen as oxidizer, and nitrogen as purge gas. The solenoid valves were employed to control intermittent supplies of kerosene, oxygen and purge gas. PDRE test model was 50 mm in inner diameter by 1.2 m long. The DDT （deflagration to detonation transition） enhancement device Shchelkin spiral was used in the test model. The effects of detonation frequency on its time-averaged thrust and specific impulse were experimentally investigated. The obtained results showes that the time-averaged thrust of PDRE test model was approximately proportional to the detonation frequency. For the detonation frequency 20 Hz, the time-averaged thrust was around 107 N, and the specific impulse was around 125 s. The nozzle experiments were conducted using PDRE test model with three traditional nozzles. The experimental results obtained demonstrated that all of those nozzles could augment the thrust and specific impulse. Among those three nozzles, the convergent nozzle had the largest increased augmentation, which was approximately 18%, under the specific condition of the experiment.

关键词： pulse detonation rocket engine impulse nozzle experimental investigation

A general tail item representation enhancement framework for sequential recommendation

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Frontiers of Computer Science 2024年第6期18卷 186333-186333页

作者： CHENG Mingyue LIU qi ZHANG Wenyu LIU Zhiding ZHAO Hongke CHEN Enhong Anhui Province Key Laboratory of Big Data Analysis and Application University of Science and Technology of China & State Key Laboratory of Cognitive Intelligence College of Management and Economics

Recently advancements in deep learning models have significantly facilitated the development of sequential recommender systems (SRS). However, the current deep model structures are limited in their ability to learn high-quality embeddings with insufficient data. Meanwhile, highly skewed long-tail distribution is very common in recommender systems. Therefore, in this paper, we focus on enhancing the representation of tail items to improve sequential recommendation performance. Through empirical studies on benchmarks, we surprisingly observe that both the ranking performance and training procedure are greatly hindered by the poorly optimized tail item embeddings. To address this issue, we propose a sequential recommendation framework named TailRec that enables contextual information of tail item well-leveraged and greatly improves its corresponding representation. Given the characteristics of the sequential recommendation task, the surrounding interaction records of each tail item are regarded as contextual information without leveraging any additional side information. This approach allows for the mining of contextual information from cross-sequence behaviors to boost the performance of sequential recommendations. Such a light contextual filtering component is plug-and-play for a series of SRS models. To verify the effectiveness of the proposed TailRec, we conduct extensive experiments over several popular benchmark recommenders. The experimental results demonstrate that TailRec can greatly improve the recommendation results and speed up the training process. The codes of our methods have been available.

关键词： sequential recommendation long-tail distribution training accelerating

Peroxisome proliferator-activated receptor α,a potential therapeutic target for alcoholic liver disease

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World Journal of Gastroenterology 2014年第25期20卷 8055-8060页

作者： Yue-Min Nan Rong-qi Wang Na Fu Department of Traditional and Western Medical Hepatology Third Hospital of Hebei Medical University

Alcoholic liver injury represents a progressive process with a range of consequences including hepatic steatosis, steatohepatitis, liver fibrosis, cirrhosis, and hepatocellular carcinoma. Targeting key molecular regulators involved in the development of alcoholic liver injury may be of great value in the prevention of liver injury. Peroxisome proliferator-activated receptor α (PPARα) plays a pivotal role in modulation of hepatic lipid metabolism, oxidative stress, inflammatory response and fibrogenesis. As such, PPARα may be a potential therapeutic target for the treatment of alcoholic liver disease.

关键词： Alcoholic liver disease Oxidative stress Inflammation Fibrosis Peroxisome proliferator-activated receptor α

Resolving the GPU responsiveness dilemma through program transformations

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Frontiers of Computer Science 2018年第3期12卷 545-559页

作者： qi ZHU Bo WU Xipeng SHEN Kai SHEN Li SHEN Zhiying WANG National Key Laboratory of High Performance Computing National University of Defense Technology Changsha 410073 China Jiangnan Institute of Computing Technology Wuxi 214083 China Department of Computer Science North Carolina State University Raleigh NC 27695 USA EECS Colorado School of Mines Golden CO 80401 USA Department of Computer Science University of Rochester Rochester NY 14627 USA

The emerging integrated CPU-GPU architectures facilitate short computational kernels to utilize GPU acceleration. Evidence has shown that, on such systems, the GPU control responsiveness （how soon the host program finds out about the completion of a GPU kernel） is essential for the overall performance. This study identifies the GPU responsiveness dilemma： host busy polling responds quickly, but at the expense of high energy consumption and interference with co-running CPU programs; interrupt-based notification minimizes energy and CPU interference costs, but suffers from substantial response delay. We present a programlevel solution that wakes up the host program in anticipation of GPU kernel completion. We systematically explore the design space of an anticipatory wakeup scheme through a timerdelayed wakeup or kernel splitting-based pre-completion notification. Experiments show that our proposed technique can achieve the best of both worlds, high responsiveness with low power and CPU costs, for a wide range of GPU workloads.

关键词： program transformation GPU integrated architecture responsiveness

Microstructure and phase transformation behavior of Mo–MoSi_2 gradient material

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Rare Metals 2015年第11期34卷 808-813页

作者： Ying-Yi Zhang Yun-Gang Li Yong-Hong qi Xue-Feng Shi State Key Laboratory of Advance Steel Processes and Products Central Iron and Steel Research Institute College of Metallurgy and Energy Hebei Union University

Mo-MoSi2gradient coating on Mo substrate was prepared by siliconizing process,using the polysilicon as silicon *** gradient layer was analyzed by the experimental results,theoretical analysis,and thermodynamic *** silicon,molybdenum content of gradient coating shows a gradual change *** reaction between silicon and molybdenum is most likely to generate Mo5Si3,then MoSi2,finally Mo3Si,but when the silicon content is excessive,the Mo5Si3and Mo3Si will react with silicon and generate *** gradient layer is mainly constituted by Si and MoSi2,only about 1/10 gradient layer is constituted by Mo5Si3and Mo3Si,and the stable existences of Mo5Si3and Mo3Si are mainly determined by the silicon *** the Mo substrate to the surface of the coating,the phase composition of gradient coating changes as follows:Mo → transition layer,Mo（main phase） + Mo3Si + Mo5Si3→intermediate layer,and MoSi2（main phase） + Mo5Si3+Si→surface layer MoSi2（main phase） + Si,and the experimental temperature has no effect on phase composition of gradient coating.

关键词： Siliconizing Mo–MoSi2 Characteristic of gradient c

Astrocytic calcium waves:unveiling their roles in sleep and arousal modulation

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Neural Regeneration Research 2024年第5期19卷 984-987页

作者： Erxi Wu Dan qi Damir Nizamutdinov Jason H.Huang Department of Neurosurgery and Neuroscience Institute Baylor Scott&White HealthTempleTXUSA Texas A&M University School of Medicine TempleTXUSA Texas A&M University School of Pharmacy College StationTXUSA LIVESTRONG Cancer Institutes and Department of Oncology Dell Medical Schoolthe University of Texas at AustinAustinTXUSA Department of Neurosurgery Baylor College of MedicineTempleTXUSA

Neuron-astrocyte interactions are vital for the brain’s *** astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in *** on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between ***,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic *** research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel *** summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical *** findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and *** astrocytic signaling pathways shows promise for treating sleep disorders and arousal *** research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders.

关键词： arousal astrocyte calcium waves locus coeruleus neuron-astrocyte interaction norepinephrine sleep wakefulness

A WD-GA-LSSVM model for rainfall-triggered landslide displacement prediction

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Journal of Mountain Science 2018年第1期15卷 156-166页

作者： ZHU Xing MA Shu-qi XU qiang LIU Wen-de State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil and Environmental Engineering Nanyang Technological University

This paper proposes a WD-GA-LSSVM model for predicting the displacement of a deepseated landslide triggered by seasonal rainfall,in which wavelet denoising(WD)is used in displacement time series of landslide to eliminate the GPS observation noise in the original data,and genetic algorithm(GA)is applied to obtain optimal parameters of least squares support vector machines(LSSVM)*** model is first trained and then evaluated by using data from a gentle dipping(~2°-5°)landslide triggered by seasonal rainfall in the southwest of *** comparisons of WD-GA-LSSVM model with Back Propagation Neural Network(BPNN)model and LSSVM are presented,*** results indicate that the adoption of WD-GA-LSSVM model significantly improves the robustness and accuracy of the displacement prediction and it provides a powerful technique for predicting the displacement of a rainfall-triggered landslide.

关键词： WD-GA-LSSVM Landslide Rainfall Displacement prediction Wavelet denoising