LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 9 of total 9

Search options

  1. Article ; Online: Identification of performance and cost in a new backwash method to clean the UF membrane: backwashing with low dosage of NaClO.

    Yang, Lian / Qiu, Haoran / Lu, Zixin / Zhang, Chunrui / Liu, Guoliang / Chang, Jiang / Wu, Congcong / Dong, Shuoxun / Yang, Shaoxia / Xiao, Feng

    Environmental science and pollution research international

    2023  Volume 30, Issue 58, Page(s) 121983–121992

    Abstract: Ultrafiltration (UF) is widely used in wastewater reclamation treatments. Conventional backwashing is usually performed at regular time intervals (10-120 min) with permeate and without the addition of chemicals. Chemical enhanced backwashing (CEB) is ... ...

    Abstract Ultrafiltration (UF) is widely used in wastewater reclamation treatments. Conventional backwashing is usually performed at regular time intervals (10-120 min) with permeate and without the addition of chemicals. Chemical enhanced backwashing (CEB) is usually applied after 70-90 filtration cycles with added chemicals. These cleaning methods cause membrane fouling and require costly chemicals. Instead of conventional backwashing, we propose herein a new backwashing method involving backwashing the effluent with low doses of sodium hypochlorite (NaClO) named as BELN. The performance and cost of UF backwashing were investigated with Beijing wastewater reclamation treatment. The results showed that the transmembrane pressure (TMP) increased from 33.2 to 48.2 kPa during hydraulic backwashing after 80 filtration cycles but increased from 33.3 to 39.3 kPa during backwashing with a low NaClO content of 20 mg/L. It was also noticed that the hydraulic-irreversible fouling index decreased from 5.58 × 10
    MeSH term(s) Ultrafiltration/methods ; Wastewater ; Membranes, Artificial ; Filtration ; Water Purification/methods
    Chemical Substances Wastewater ; Membranes, Artificial
    Language English
    Publishing date 2023-11-14
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-023-31008-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 5915: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Article: Tandem Electrocatalytic CO₂ Reduction with Efficient Intermediate Conversion over Pyramid-Textured Cu–Ag Catalysts

    Liu, Ya / Qiu, Haoran / Li, Jinghan / Guo, Liejin / Ager, Joel W.

    ACS applied materials & interfaces. 2021 Aug. 18, v. 13, no. 34

    2021  

    Abstract: If combined with renewably generated electricity, electrochemical CO₂ reduction (E-CO₂R) could be used as a sustainable source of chemicals and fuels. Tandem catalysis approaches are attractive for providing the product selectivity, which would be ... ...

    Abstract If combined with renewably generated electricity, electrochemical CO₂ reduction (E-CO₂R) could be used as a sustainable source of chemicals and fuels. Tandem catalysis approaches are attractive for providing the product selectivity, which would be required for commercial applications. Here, we demonstrate a two-step tandem electrocatalytic E-CO₂R with efficient conversion of the intermediate species. The catalyst scaffold is Si(100), which is etched to form a textured surface consisting of micron-sized pyramid structures with the {111} facets. Two metals are used in the electrocatalytic cascade: Ag is employed to perform a two-electron reduction of CO₂ to the intermediate CO, and Cu performs conversion to more reduced products. Using high-angle physical vapor deposition, we form separated, micron-scale areas of the two electrocatalysts on opposite sides of the pyramids, with their relative surface coverages being tunable with the deposition angle. Compared to the textured scaffolds with blanket Ag and Cu used as controls, bimetallic pyramid tandem catalysts have higher current densities and much lower faradic efficiencies (FE) for CO. These effects are due to efficient conversion of the CO formed on Ag to more reduced products on Cu. Methane is the main product to be enhanced by the cascade pathway: a bimetallic catalyst with approximately equal coverages of Ag and Cu produces methane with a FE of 62% at −1.1 VRHE, corresponding to a partial current density of 12.7 mA cm–². We estimate an intermediate conversion yield for the CO intermediate of 80–90%, which is close to the mass-transport limited value predicted by reaction-diffusion simulations.
    Keywords carbon dioxide ; catalysts ; catalytic activity ; electricity ; electrochemistry ; methane ; vapors
    Language English
    Dates of publication 2021-0818
    Size p. 40513-40521.
    Publishing place American Chemical Society
    Document type Article
    ISSN 1944-8252
    DOI 10.1021/acsami.1c08688
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  3. Article ; Online: Tandem Electrocatalytic CO

    Liu, Ya / Qiu, Haoran / Li, Jinghan / Guo, Liejin / Ager, Joel W

    ACS applied materials & interfaces

    2021  Volume 13, Issue 34, Page(s) 40513–40521

    Abstract: If combined with renewably generated electricity, electrochemical ... ...

    Abstract If combined with renewably generated electricity, electrochemical CO
    Language English
    Publishing date 2021-08-18
    Publishing country United States
    Document type Journal Article
    ISSN 1944-8252
    ISSN (online) 1944-8252
    DOI 10.1021/acsami.1c08688
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  4. Book ; Online: SLO beyond the Hardware Isolation Limits

    Qiu, Haoran / Chen, Yongzhou / Xu, Tianyin / Kalbarczyk, Zbigniew T. / Iyer, Ravishankar K.

    2021  

    Abstract: Performance isolation is a keystone for SLO guarantees with shared resources in cloud and datacenter environments. To meet SLO requirements, the state of the art relies on hardware QoS support (e.g., Intel RDT) to allocate shared resources such as last- ... ...

    Abstract Performance isolation is a keystone for SLO guarantees with shared resources in cloud and datacenter environments. To meet SLO requirements, the state of the art relies on hardware QoS support (e.g., Intel RDT) to allocate shared resources such as last-level caches and memory bandwidth for co-located latency-critical applications. As a result, the number of latency-critical applications that can be deployed on a physical machine is bounded by the hardware allocation capability. Unfortunately, such hardware capability is very limited. For example, Intel Xeon E5 v3 processors support at most four partitions for last-level caches, i.e., at most four applications can have dedicated resource allocation. This paper discusses the feasibility and unexplored challenges of providing SLO guarantees beyond the limits of hardware capability. We present CoCo to show the feasibility and the benefits. CoCo schedules applications to time-share interference-free partitions as a transparent software layer. Our evaluation shows that CoCo outperforms non-partitioned and round-robin approaches by up to 9x and 1.2x.
    Keywords Computer Science - Operating Systems ; Computer Science - Performance
    Subject code 004
    Publishing date 2021-09-23
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  5. Book ; Online: FIRM

    Qiu, Haoran / Banerjee, Subho S. / Jha, Saurabh / Kalbarczyk, Zbigniew T. / Iyer, Ravishankar K.

    An Intelligent Fine-Grained Resource Management Framework for SLO-Oriented Microservices

    2020  

    Abstract: Modern user-facing, latency-sensitive web services include numerous distributed, intercommunicating microservices that promise to simplify software development and operation. However, multiplexing compute-resources across microservices is still ... ...

    Abstract Modern user-facing, latency-sensitive web services include numerous distributed, intercommunicating microservices that promise to simplify software development and operation. However, multiplexing compute-resources across microservices is still challenging in production because contention for shared resources can cause latency spikes that violate the service-level objectives (SLOs) of user requests. This paper presents FIRM, an intelligent fine-grained resource management framework for predictable sharing of resources across microservices to drive up overall utilization. FIRM leverages online telemetry data and machine-learning methods to adaptively (a) detect/localize microservices that cause SLO-violations, (b) identify low-level resources in contention, and (c) take actions to mitigate SLO-violations by dynamic reprovisioning. Experiments across four microservice benchmarks demonstrate that FIRM reduces SLO violations by up to 16x while reducing the overall requested CPU limit by up to 62%. Moreover, FIRM improves performance predictability by reducing tail latencies by up to 11x.

    Comment: This is a draft version of the paper accepted in OSDI '20
    Keywords Computer Science - Distributed ; Parallel ; and Cluster Computing ; Computer Science - Performance
    Subject code 006
    Publishing date 2020-08-19
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article: Distribution of polycyclic aromatic hydrocarbons in surface water from the upper reach of the Yellow River, Northwestern China

    Zhao, Xia / Qiu, Haoran / Zhao, Yangli / Shen, Jimin / Chen, Zhonglin / Chen, Jixiang

    Environmental science and pollution research international. 2015 May, v. 22, no. 9

    2015  

    Abstract: The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ... ...

    Abstract The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ng/L in water, 1502 to 11,562 ng/g in SPMs, and 181 to 1583 ng/g in sediments. The compositions of PAHs showed that 2- to 3-ring PAHs were abundant in water, 2- to 4-ring PAHs were predominant in SPMs, and 2- to 5-ring PAHs were abundant in sediments. The spatial distribution of PAHs was site-specific and PAHs varied at different sampling locations. The diagnostic ratio analysis indicated that the PAHs mainly had a pyrolytic source. The ecological risk assessment showed that the ecosystem risk of PAHs was low in the Lanzhou reach of the Yellow River.
    Keywords ecosystems ; environmental assessment ; polycyclic aromatic hydrocarbons ; risk ; sediments ; surface water ; China ; Yellow River
    Language English
    Dates of publication 2015-05
    Size p. 6950-6956.
    Publishing place Springer-Verlag
    Document type Article
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-014-3846-z
    Database NAL-Catalogue (AGRICOLA)

    Full text online

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 5915: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  7. Book ; Online: Application-aware Congestion Mitigation for High-Performance Computing Systems

    Patke, Archit / Jha, Saurabh / Qiu, Haoran / Brandt, Jim / Gentile, Ann / Greenseid, Joe / Kalbarczyk, Zbigniew / Iyer, Ravishankar

    2020  

    Abstract: High-performance computing (HPC) systems frequently experience congestion leading to significant application performance variation. However, the impact of congestion on application runtime differs from application to application depending on their ... ...

    Abstract High-performance computing (HPC) systems frequently experience congestion leading to significant application performance variation. However, the impact of congestion on application runtime differs from application to application depending on their network characteristics (such as bandwidth and latency requirements). We leverage this insight to develop Netscope, an automated ML-driven framework that considers those network characteristics to dynamically mitigate congestion. We evaluate Netscope on four Cray Aries systems, including a production supercomputer on real scientific applications. Netscope has a lower training cost and accurately estimates the impact of congestion on application runtime with a correlation between 0.7and 0.9 for common scientific applications. Moreover, we find that Netscope reduces tail runtime variability by up to 14.9 times while improving median system utility by 12%.
    Keywords Computer Science - Distributed ; Parallel ; and Cluster Computing ; Computer Science - Networking and Internet Architecture
    Subject code 000
    Publishing date 2020-12-14
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  8. Article ; Online: Distribution of polycyclic aromatic hydrocarbons in surface water from the upper reach of the Yellow River, Northwestern China.

    Zhao, Xia / Qiu, Haoran / Zhao, Yangli / Shen, Jimin / Chen, Zhonglin / Chen, Jixiang

    Environmental science and pollution research international

    2015  Volume 22, Issue 9, Page(s) 6950–6956

    Abstract: The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ... ...

    Abstract The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ng/L in water, 1502 to 11,562 ng/g in SPMs, and 181 to 1583 ng/g in sediments. The compositions of PAHs showed that 2- to 3-ring PAHs were abundant in water, 2- to 4-ring PAHs were predominant in SPMs, and 2- to 5-ring PAHs were abundant in sediments. The spatial distribution of PAHs was site-specific and PAHs varied at different sampling locations. The diagnostic ratio analysis indicated that the PAHs mainly had a pyrolytic source. The ecological risk assessment showed that the ecosystem risk of PAHs was low in the Lanzhou reach of the Yellow River.
    MeSH term(s) China ; Ecology ; Ecosystem ; Environmental Monitoring ; Geologic Sediments/analysis ; Particulate Matter/analysis ; Polycyclic Aromatic Hydrocarbons/analysis ; Risk Assessment ; Rivers/chemistry ; Water/analysis ; Water Pollutants, Chemical/analysis
    Chemical Substances Particulate Matter ; Polycyclic Aromatic Hydrocarbons ; Water Pollutants, Chemical ; Water (059QF0KO0R)
    Language English
    Publishing date 2015-05
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-014-3846-z
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 5915: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  9. Article: Distribution of polycyclic aromatic hydrocarbons in surface water from the upper reach of the Yellow River, Northwestern China

    Zhao, Xia / Qiu, Haoran / Zhao, Yangli / Shen, Jimin / Chen, Zhonglin / Chen, Jixiang

    Environmental science and pollution research international

    Volume v. 22,, Issue no. 9

    Abstract: The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ... ...

    Abstract The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matters (SPMs), and sediments in the Lanzhou reach of the Yellow River were investigated in this study. The total PAH concentrations ranged from 548 to 2598 ng/L in water, 1502 to 11,562 ng/g in SPMs, and 181 to 1583 ng/g in sediments. The compositions of PAHs showed that 2- to 3-ring PAHs were abundant in water, 2- to 4-ring PAHs were predominant in SPMs, and 2- to 5-ring PAHs were abundant in sediments. The spatial distribution of PAHs was site-specific and PAHs varied at different sampling locations. The diagnostic ratio analysis indicated that the PAHs mainly had a pyrolytic source. The ecological risk assessment showed that the ecosystem risk of PAHs was low in the Lanzhou reach of the Yellow River.
    Keywords risk ; surface water ; sediments ; polycyclic aromatic hydrocarbons ; environmental assessment ; ecosystems
    Language English
    Document type Article
    ISSN 0944-1344
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top