scholarly journals Preparation and Performance of Structure Controllable Biochar Obtained From Cattail-Sludge Composites

Author(s):  
Fanfan Liang ◽  
Yan Wang

Abstract Biochar obtained from cattail-sludge composites (BC/CS) was treated as a raw material, with monopotassium phosphate and ammonium chloride solution as absorbents, to find the best parameters for the preparation of structure controllable biochar (BC/SC). Slow pyrolysis and single factor experiment method were employed in the preparation of BC/CS and BC/SC, with EA, BET and SEM to illustrate the performance of BC/SC. The results showed that the best parameters for BC/CS were characterized by a ratio of cattail-sludge composites (60:40, wt%), a charring temperature of 500℃, a charring time of 0.5 hrs, KOH as an activator, an immersion ratio of 4 mL·g-1, an activation concentration of 300 g·L-1 and an immersion time of 6 hrs; the best parameters for BC/SC contained a sizing amount of 60%, a molding pressure, temperature and time of 5 N (cm2)-1, 160℃, and 95 min, respectively; compared to BC/CS, BC/SC was characterized by a higher content of H but a lower O content, leading to the increase in its hydrophobicity and stability; in addition, the addition of polyethylene enabled an increase in the pore diameter of BC/SC and a close bond with particles on the surface. Meanwhile, in BC/SC, the surface functional groups of CH3 and C—O—C were reduced in their contents, in contrast to a large amount of C crystals on its surface. Such results could provide a new process for resource recycling of cattail and sludge, as well as evidence for material selection in the treatment of eutrophication water bodies.

2014 ◽  
Vol 599 ◽  
pp. 338-345 ◽  
Author(s):  
Jia Miao Ni ◽  
Xiu Jian Zhao ◽  
Bin Bin Li ◽  
Min Dong Zheng ◽  
Ting Peng

To obtain high quality SnO2 film, high conductivity and high quality SnO2 target should be obtained first. In this paper, high-conductivity Sb: SnO2 (ATO) ceramic targets were fabricated using SnO2, Sb2O3 powder as raw material. The chemical composition and morphology of SnO2 targets were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The effect of different forming pressure on the morphology and electrical properties of targets were studied in our paper. The results show that molding pressure has a significant impact on the density of ATO targets and performance during sintering process. When molding pressure is 15 Mpa, the target has the minimum resistivity for 2.38 Ωcm. XRD results show that ATO target possess tetragonal rutile structure with the preferred orientation of (101). XPS indicate that the chemical state of Sn element in the target is Sn4+ and that of Sb is Sb3+. In addition, the shrinkage rate of conductive SnO2 target is 10.34% so that target can be used to sputtering in the magnetron sputter. The preparation process is simple and cost of SnO2 target is low. The transparent conductive SnO2 thin film was successfully deposited on glass substrate with good performance of high hole concentration and low resistivity of 3.334×1019 cm-3 and 3.588 Ω·cm, respectively. The average transmission of p-type SnO2 films was above 80% in the visible light range.


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3515
Author(s):  
Weikang Wang ◽  
Xuanchun Wei ◽  
Xinhua Cai ◽  
Hongyang Deng ◽  
Bokang Li

: The early-age carbonation curing technique is an effective way to improve the performance of cement-based materials and reduce their carbon footprint. This work investigates the early mechanical properties and microstructure of calcium sulfoaluminate (CSA) cement specimens under early-age carbonation curing, considering five factors: briquetting pressure, water–binder (w/b) ratio, starting point of carbonation curing, carbonation curing time, and carbonation curing pressure. The carbonization process and performance enhancement mechanism of CSA cement are analyzed by mercury intrusion porosimetry (MIP), thermogravimetry and derivative thermogravimetry (TG-DTG) analysis, X-ray diffraction (XRD), and scanning electron microscope (SEM). The results show that early-age carbonation curing can accelerate the hardening speed of CSA cement paste, reduce the cumulative porosity of the cement paste, refine the pore diameter distribution, and make the pore diameter distribution more uniform, thus greatly improving the early compressive strength of the paste. The most favorable w/b ratio for the carbonization reaction of CSA cement paste is between 0.15 and 0.2; the most suitable carbonation curing starting time point is 4 h after initial hydration; the carbonation curing pressure should be between 3 and 4 bar; and the most appropriate time for carbonation curing is between 6 and 12 h.


2013 ◽  
Vol 448-453 ◽  
pp. 786-790
Author(s):  
Wei Gao ◽  
Rong Fei Zhao ◽  
Qing Yu Liu ◽  
Xu Wei Bai

This paper take link mold pellet pelletizer to carry on the pellet fuel manufacture experiment with corn straw stalk. The influence of moisture content, material size and fermentation time impact on broken strength is studied by single factor experiment. Through quadratic regression orthogonal rotating combination experiment, establish mathematics equation of the factors and the straw pellet fuel broken strength and analyze the important degree of each experimental factor impact on the granulation rate. Through the optimized computation, definite optimization parameter of the highest broken strength is that raw material moisture content is 20%, fermentation time is 4h and particle size is 2.5mm. The result of verifying experiment indicat that the optimal parameter combination and the predict data measured were consistent.


Author(s):  
Barbara Widera

The paper addresses the topic of nature-based solutions applied in the architectural and urban design. These ideas are analyzed in the context of the opportunities they create for the humanity in terms of the sustainable growth and environmental protection. Nature-based solutions are inherently taken from nature. The first part of the paper presents their tremendous potential to be energy and resource-efficient, and resilient to change. In the second part of the research particular concepts driven from nature (copied form nature or inspired by nature) proposed for the buildings and cities are described and evaluated. The author discusses their functional usefulness, spatial appropriateness, adaptation to local conditions, end-user comfort, environmental benefits and the possibility of duplication. Nature-based solutions applied in urban planning can make cities more climate resilient and contribute to ecosystems restoration. The paper describes how sustainable urbanization can stimulate economic growth, make cities more attractive and enhance well-being of the inhabitants. It is also explained how particular buildings can benefit from the concepts driven from nature e.g. by increasing their energy efficiency and performance in terms of raw material consumption. In purpose to properly response to the climate challenge, humanity has to establish a new kind of partnership with nature. Using nature-based solutions should be considered as an important part of this approach. The concepts presented in this paper show some of the most promising options, such as integration of living systems with built systems and innovative combinations of soft and hard engineering. In conclusion some of the most promising nature-based solutions for climate resilient buildings and cities are indicated


2021 ◽  
Vol 17 ◽  
Author(s):  
Xiaoting Wang ◽  
Yingdong Yang ◽  
Tianyou Wang ◽  
Dian Chen ◽  
Wugan Luo

Background: Bronze spears are weapons with unique regional characteristics of the Shu culture, Southwest China in the Bronze Age, which reflect the bronze manufacturing tradition and the utilization of mineral resources of ancestors. Previous studies mainly focused on the classification, the alloy composition or the production of bronze spearheads of the Shu culture. The purpose of this paper was to make a comprehensive discussion on the Shu culture from the aspects of the relationship between typology and scientific characteristics, the differences in metal raw material selection with the Ba culture, and the contact with the culture in the Central Plains. Results : Methods: In this study, typology, portable X-ray fluorescence spectrometry (pXRF) and multi collector inductively coupled plasma mass spectrometry (MC-ICP-MS) were used to analyze thirteen bronze spearheads unearthed from Shuangyuan site, an Eastern Zhou cemetery in Chengdu City, Sichuan Province, Southwest China. Methods: The results show that the spearheads can be classified into three types in typology. All samples are tin-lead ternary bronzes, and the lead isotope data indicate the lead ore. Most spearheads show ordinary lead and only one spearhead has highly radiogenic lead. Conclusion: The typical Shu-style bronze spearheads have distinct shapes but similar ore materials. Meanwhile, people of the Ba culture and the Shu culture used different metal sources to make bronze spearheads. In addition, a very special bronze spearhead suggests that ancestors of the Shu culture in the Eastern Zhou Dynasty imitated the late Shang culture in the Central Plains.


Author(s):  
Amit Agrawal

The Supply Chain Improvement (SCO) project is being introduced by KNPC, which recognises the major business advantages of improved hydrocarbon supply chain efficiency. The objectives of this work is to strengthen, optimise, and integrate supply scheduling and processes not just at stage of enterprise, but also throughout the entire KNPC framework. This is expected to lead to an improvement in the company's bottom line and facilitate the management of business operations at the highest level of efficiency, agility and profitability. In ever changing market conditions and globally competitiveness, it is necessary that raw material supply storage and product delivery were carried out at the lowest possible time and efficiency. Otherwise export oriented refinery like KNPC cannot remain in business with profit. KNPC has therefore embarked on ambitious multi-year operational excellence programs aimed at enhancing its operations and business processes that include short / mid-term planning, scheduling, accounting for growth, inventory management, and performance management. The aim is to achieve top-quartile financial results by accessing new value streams, encapsulating business processes of best practice and motivating employees of businesses to work in a collaborative atmosphere within the global and cross-functional business cycle to make smarter, quicker and more competitive choices.


2014 ◽  
Vol 509 ◽  
pp. 118-122 ◽  
Author(s):  
Jian Hui Ma ◽  
Peng Guo

At present, the control of the automobile engine exhaust noise is mainly installed exhaust muffler. Muffler design and performance research mainly around the silencing performance and the influence to engine power loss. This article built the 3d modeling of automobile exhaust muffler and through simulation analysis obtained the muffler internal acoustic pressure distribution and changes of insertion loss with frequency. Predict the silencer muffler performance as well as the influence on engine power loss. Provide a reference basis for the design of the silencer and optimization. Compared to the traditional experiment method, the method in this article has the advantages of short cycle, low cost.


2014 ◽  
Vol 788 ◽  
pp. 28-33
Author(s):  
Peng Deng ◽  
Yu Qin Liu ◽  
Wen Gui Yao ◽  
Hong Wen Ma

In this paper, a new process for the production of the primary magnesium is introduced using the dolomite as the raw material. The magnesia and calcium carbonate were prepared from dolomite by acidification. The content of magnesium oxide can reach 98.92% about the magnesia obtained. The magnesia is used to produce primary magnesium by aluminothermic reduction under vacuum condition. The reduction ratio of MgO can be up to 86.14% under the temperature of 1200°C for 5hrs, briquetting pressure of 10MPa and the molar ratio of MgO to Al of 3:2. The content of magnesium is more than 99.90%. The major phases in the briquette residue are corundum and spinel, which can be used as refractory.


Antiquity ◽  
2000 ◽  
Vol 74 (284) ◽  
pp. 372-379 ◽  
Author(s):  
S. Miller-Antonio ◽  
L. A. Schepartz ◽  
D. Bakken

Research in Dadong Cave, southern China, has revealed evidence suggesting that nonlithic materials were used in the tool kits of the Chinese Lower Palaeolithic.


Sign in / Sign up

Export Citation Format

Share Document