A field investigation of the relationship between zinc and acid volatile sulfide concentrations in freshwater sediments

It has become the main way for heavy industry enterprises to decrease the cost to excavate “logistics resources” according to the Systematic Layout Planning (SLP). Taking the new tool shaft machining workshop of Luoyang yituo zhongcheng machinery co., LTD. as an example, through the method of field investigation and visit, we get the data of the process flow, material handling, the relationship between each process and the general situation of the new workshop. The SLP method is used to divide the work units in the workshop, analyze the relationship between logistics and non-logistics among each work unit, determine the comprehensive relationship between each operation unit, and make the position correlation diagram. Besides, we also combine the current situation of the workshop to sort out the layout scheme to reduce the production costs of the workshop.

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A Field Investigation of the Relationship Between Length of Tow, Size of Net and Sampling Error

ICES Journal of Marine Science ◽

10.1093/icesjms/34.2.268 ◽

1972 ◽

Vol 34 (2) ◽

pp. 268-275 ◽

Cited By ~ 17

Author(s):

P. H. Wiebe

Keyword(s):

Sampling Error ◽

Field Investigation ◽

The Relationship

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Theoretical Study on the Relationship of Building Thermal Insulation with Indoor Thermal Comfort Based on APMV Index and Energy Consumption of Rural Residential Buildings

Applied Sciences ◽

10.3390/app11188565 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8565

Author(s):

Jinzhe Nie ◽

Yuxin Pang ◽

Congcong Wang ◽

Han Zhang ◽

Kuichao Yin

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Indoor Air ◽

Residential Buildings ◽

Field Investigation ◽

Energy And Environment ◽

Indoor Thermal Comfort ◽

Adaptive Thermal Comfort ◽

Insulation Thickness ◽

The Relationship

In the field investigation of rural dwellings, it was found that thermal feelings are significantly different with varied envelopes even under the same indoor air temperature, and this paper explores the phenomenon in simulation. Based on building thermal investigations in several villages of North China, a typical energy and environment simulation model for rural residences was developed using DeST, and the hourly parameters of temperature and humidity were used to calculate the adaptive thermal comfort (APMV) of the rooms. The results show that the main reason for the different thermal comfort at the same air temperature is the large difference in the inner surface temperature. By adjusting the insulation thickness of the envelope structure, the relationship between it and the APMV value is obtained. By adjusting the insulation thickness of the enclosure structure and getting the correlation between it and the APMV value, it is obtained that when the heat transfer coefficient of the enclosure structure meets 0.5 W/ (m2−K), the indoors can be in thermal comfort. This paper considers that the indoor air temperature cannot represent the APMV to evaluate the indoor thermal comfort, and the APMV value should be used to evaluate the thermal comfort of the renovated building and calculate the corresponding energy saving rate.

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Sulfur Development in the Water-Sediment System of the Algae Accumulation Embay Area in Lake Taihu

Water ◽

10.3390/w11091817 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1817 ◽

Cited By ~ 1

Author(s):

Cheng Liu ◽

Shiguang Shao ◽

Lei Zhang ◽

Yiheng Du ◽

Kaining Chen ◽

...

Keyword(s):

Surface Sediments ◽

Lake Taihu ◽

Field Investigation ◽

Acid Volatile Sulfide ◽

Short Term ◽

Overlying Water ◽

Eutrophication Control ◽

Algae Blooms ◽

Water And Sediment ◽

Eutrophic Shallow Lakes

Sulfur development in water-sediment systems is closely related to eutrophication and harmful algae blooms (HABs). However, the development of sulfur in water-sediment systems during heavy algae accumulation still remains unclear, especially in hyper-eutrophic shallow lakes. In this study, a quarterly field investigation was carried out for a year in the algae accumulated embay area of Lake Taihu, accompanied by a short-term laboratory experiment on algae accumulation. The results show that hydrogen sulfide and methanethiol dominated the volatile sulfur compounds (VSCs) in the water during non-accumulation seasons, whereas the concentrations of dimethyl sulfides increased during heavy algae accumulation, both in the field and the laboratory. An increase in the acid volatile sulfide (AVS) in the surface sediments was also discovered together with the increase in dimethyl sulfides. The depletion of oxygen in the overlying water and sediment–water interface during the heavy algae accumulation and decomposition was found to be closely related to both the increase in VSCs in the overlying water and increase in AVS in the sediment. The increased concentrations of these reductive sulfocompounds might aggravate the eutrophication and HABs and should be given more consideration in future eutrophication control plans for lakes.

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Field Investigation of Blasting-Induced Vibration in Concrete Linings during Expansion of Old Highway Tunnel

Advances in Civil Engineering ◽

10.1155/2021/8820544 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Ya-Qiong Wang ◽

Lin-Jin Gong ◽

Nan-Nan An ◽

Xing-Bin Peng ◽

Wei Wang ◽

...

Keyword(s):

Regression Analysis ◽

Particle Velocity ◽

Vibration Frequency ◽

Empirical Formula ◽

Field Investigation ◽

Primary Method ◽

Design Standards ◽

Highway Tunnel ◽

The Relationship ◽

Blasting Method

Numerous mountain highway tunnels in China do not satisfy the current traffic design standards and therefore need to be rebuilt or expanded. The drilling-blasting method is the primary method employed in China for expanding mountain highway tunnels, and it is crucial to monitor the vibrations caused by blasting. This study conducted a field investigation of the vibrations caused by blasting during the expansion of Yujiaya tunnel, which was built in 1999. The blasting-induced vibrations in the new and old concrete linings were monitored and analyzed during the expansion. The measured values of the peak particle velocity (PPV) varied within the range of 0.097–8.246 cm/s. The attenuation law of the PPV was determined via a regression analysis using Sadovsky’s empirical formula. The relationship between the main vibration frequency and the distance from the blasting source was expressed as a power function. Finally, the safety distances of the concrete linings subject to blasting vibrations were analyzed and discussed.

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Sediment-trapping eﬀectiveness of check dams with multiple debris-flow surges: Experimental study

10.5194/egusphere-egu21-9144 ◽

2021 ◽

Author(s):

Jiangang Chen ◽

Xi'an Wang ◽

Huayong Chen

Keyword(s):

Debris Flow ◽

Field Investigation ◽

Sediment Deposition ◽

Disaster Mitigation ◽

Check Dam ◽

Sediment Trapping ◽

Check Dams ◽

The Relationship ◽

Debris Flow Hazard ◽

Deposition Morphology

<p>A series of check dams were constructed for debris-flow hazard mitigation in China. Based on the results of field investigation, check dam has a significant impact on the geomorphology of debris flow gully, especially the upstream and downstream of a check dam. According to the relationship between the sediment deposition thickness and the check dam height, the running status of a check dam can be divided into three states: without sediment deposition, half of the storage capacity with sediment deposition, and full of sediment deposition. With the accumulation of sediment transport, the running state of a check dam gradually changed and the sediment-trapping effect of check dams has gradually weakened, leading to the loss of part of the disaster mitigation effect, increasing the risk of downstream infrastructure and human security. Therefore, experiments with multi-surges of debris flows were carried out to study the geomorphic and sediment-trapping e&#64256;ectiveness of check dams. The results showed that with the increase of the sediment amount with multi-surges, the deposition slope in the downstream dam approached or even exceeded that of upstream dam. For one surge, deposition morphology has slightly difference in the cascade dams. At last, a method for calculating the reduction coefficient of deposition slope considering the check dam height and sediment amount with multi-surges is proposed.</p>

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Climate Change Adaptations for Food Security in Vulnerable Areas of the Egyptian Nile—For Tackling the Overlooked Nexus Hazards of Hydrological Extremes and Waste Pollutions

Water ◽

10.3390/w13040412 ◽

2021 ◽

Vol 13 (4) ◽

pp. 412

Author(s):

Otto Chen ◽

Ahmed Abdelhalim ◽

Ying Liu ◽

Miguel Rico-Ramirez ◽

Dawei Han

Keyword(s):

Climate Change ◽

Food Security ◽

Solid Waste Management ◽

Nile Delta ◽

Field Investigation ◽

Hydrological Extremes ◽

Extensive Field ◽

Extreme Hydrological Events ◽

Systemic Problems ◽

The Relationship

The Nile Delta has been suffering from complex environmental hazards caused by climate change and human-induced evolvements, which have led to adverse impacts on national food security. An unfavourable nexus between solid waste management issues and extreme hydrological events is examined mainly through extensive field investigation and literature research, which is an emerging issue affecting food safety and security whilst still being overlooked so far. The findings not only reveal the significance of the emerging issue but also support our proposed recommendations in the policy/legislation and technology sphere. This interdisciplinary research employs a holistic lens that covers diverse perspectives, including systemic problems, wastewater treatment, and environmental neuroscience, to explore the relationship between food, climate change, water management, and waste pollution, and to achieve novel discoveries for the practical adaptations of Egypt’s challenges.

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Modification of metal partitioning by supplementing acid volatile sulfide in freshwater sediments

Environmental Toxicology and Chemistry ◽

10.1002/etc.5620180507 ◽

1999 ◽

Vol 18 (5) ◽

pp. 858-864 ◽

Cited By ~ 11

Author(s):

Edward N. Leonard ◽

David R. Mount ◽

Gerald T. Ankley

Keyword(s):

Acid Volatile Sulfide ◽

Metal Partitioning ◽

Freshwater Sediments

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Geochemistry of hydrothermally altered rocks with gold mineralization hosted in alkaline complex in Hongshan area, Taihang Orogen, North China

World Journal of Engineering ◽

10.1108/wje-02-2016-001 ◽

2016 ◽

Vol 13 (1) ◽

pp. 23-34

Author(s):

Jingsen Zhang ◽

Jing Zhang ◽

Yanchao Zhai

Keyword(s):

Hydrothermal Alteration ◽

Design Methodology ◽

North China ◽

Gold Mineralization ◽

Field Investigation ◽

Fracture Zones ◽

Loss On Ignition ◽

Alkaline Complex ◽

Content Type ◽

The Relationship

Purpose This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration. Design/methodology/approach Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer. Findings Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe2O3 replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

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