Research Progress of Nitrite Corrosion Inhibitor in Concrete

Nitrite inhibitor is a kind of most effective inhibitory corrosion additive used in reinforced concrete. This paper expounded the inhibiting mechanism and physical property of nitrite in concrete. Moreover, the recent progress and application condition at home and abroad were summarized. Meanwhile, corresponding methods for detecting nitrite ion concentration is proposed. Additionally, the inhibition practice on corrosion protection of reinforcing bar in concrete was presented. The long-term inhibiting effectiveness of nitrite ion in concrete when the n(NO2-)/n(Cl-) ratios were above the threshold values in concrete was obtained. Finally it is confirmed that critical molar ratio of n(NO2-)/n(Cl-) increased with differential nitrite ion concentration, higher cathode, and anode area ratio in steel bar.

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BrO/SO<sub>2</sub> molar ratios from scanning DOAS measurements in the NOVAC network

Solid Earth Discussions ◽

10.5194/sed-5-1845-2013 ◽

2013 ◽

Vol 5 (2) ◽

pp. 1845-1870 ◽

Cited By ~ 3

Author(s):

P. Lübcke ◽

N. Bobrowski ◽

S. Arellano ◽

B. Galle ◽

G. Garzón ◽

...

Keyword(s):

Molar Ratio ◽

Optical Absorption Spectroscopy ◽

Short Term ◽

Dynamic Changes ◽

Volcanic System ◽

Molar Ratios ◽

Remote Sensing Technique ◽

Field Campaigns ◽

Term Field

Abstract. The molar ratio of BrO to SO2 is, like other halogen/sulphur ratios, a~possible precursor for dynamic changes in the shallow part of a volcanic system. While the predictive significance of the BrO/SO2 ratio has not been well constrained yet, it has the major advantage that this ratio can be readily measured using the remote-sensing technique Differential Optical Absorption Spectroscopy (DOAS) in the UV. While BrO/SO2 ratios have been measured during several short-term field campaigns this article presents an algorithm that can be used to obtain long-term time series of BrO/SO2 ratios from the scanning DOAS instruments of the Network for Observation of Volcanic and Atmospheric Change (NOVAC) or comparable networks. Parameters of the DOAS retrieval of both trace gases are given and the influence of co-adding spectra on the retrieval error will be investigated. Difficulties in the evaluation of spectroscopic data from monitoring instruments in volcanic environments and possible solutions are discussed. The new algorithm is demonstrated by evaluating data from the NOVAC scanning DOAS systems at Nevado del Ruiz, Colombia encompassing almost four years of measurements between November 2009 and end of June 2013. This dataset shows variations of the BrO/SO2 ratio several weeks prior to the eruption on 30 June 2012.

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Proton Conducting Electrolytes Synthesized with Diammonium Hydrogen Phosphate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.421-422.471 ◽

2009 ◽

Vol 421-422 ◽

pp. 471-474 ◽

Cited By ~ 1

Author(s):

Dedy Eka Priyanto ◽

Hidenobu Shiroishi ◽

Satoshi Tanimoto ◽

Shunsuke Hirukawa ◽

Morihiro Saito ◽

...

Keyword(s):

Solid State ◽

Impedance Spectroscopy ◽

Molar Ratio ◽

Preparation Process ◽

Ac Impedance Spectroscopy ◽

Hydrogen Phosphate ◽

Proton Conducting ◽

Diammonium Hydrogen Phosphate ◽

Diammonium Hydrogen

Proton conducting ZrO2－yP2O5 (y = 1.0, 1.2, 1.4. 1.6, 1.8) electrolytes based on a shell-core structure were synthesized with diammonium hydrogen phosphate by a solid state reaction, and their conductivities were investigated by ac-impedance spectroscopy. Among the ZrO2-yP2O5 compositions, ZrO2－1.6P2O5 showed the highest proton conductivity of 0.13 Scm-1 at 250°C. The conductivity increased with increasing P2O5 molar ratio and were significantly influenced by heat-treatments in the preparation process. Polytetraflouroethylene (PTFE) was also mixed into these electrolytes in order to improve the mechanical strength and long term durability.

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A Comprehensive Evaluation of Rejuvenator on Mechanical Properties, Durability, and Dynamic Characteristics of Artificially Aged Asphalt Mixture

Materials ◽

10.3390/ma11091554 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1554 ◽

Cited By ~ 9

Author(s):

Pan Pan ◽

Yi Kuang ◽

Xiaodi Hu ◽

Xiao Zhang

Keyword(s):

Mechanical Properties ◽

Dynamic Characteristics ◽

Comprehensive Evaluation ◽

Asphalt Binder ◽

Asphalt Mixture ◽

Physical Property ◽

Fatigue Property ◽

Physical Test ◽

Aged Asphalt

In this study, the aged asphalt binder and mixture were laboratory prepared through short-term ageing testing and long-term ageing testing. Firstly, the effect of rejuvenator on physical properties of aged asphalt binders was investigated. In addition, a series of laboratory tests were performed to evaluate the influence of ageing and rejuvenator content on the mechanical properties, durability and dynamic characteristics of asphalt mixtures. Physical test results of asphalt binder testified that rejuvenator used can efficiently recover the aged asphalt binder. However, the effect of ageing and rejuvenator content exhibits different trends depending on the physical property tests conducted. Moreover, artificially aged asphalt mixture with rejuvenator has better ability to resist moisture damage and ravelling. In addition, the ITSR value is more suitable to evaluate the moisture susceptibility for asphalt recycling. Although rejuvenator improves the thermal cracking resistance and fatigue property of aged asphalt mixture, rejuvenated mixture shows greater modulus and inferior ability to resist reflective cracking than the unaged mixture. Moreover, rejuvenated mixture shows less dependence on frequency at high temperature regions and stronger dependence at low temperature regions compared to unaged and long-term aged mixtures.

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Influence of Mineral Admixtures on Corrosion Inhibition Effect of Nitrites

International Journal of Corrosion ◽

10.1155/2018/2537634 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Mengna Yang ◽

Junzhe Liu ◽

Hui Wang ◽

Yushun Li ◽

Yanhua Dai ◽

...

Keyword(s):

Fly Ash ◽

Corrosion Inhibition ◽

Ion Concentration ◽

Mineral Admixtures ◽

X Ray Diffraction ◽

Nitrite Ion ◽

X Ray ◽

Inhibition Effect ◽

Diffraction Patterns ◽

Micro Analysis

Chemical quantitative analysis of effective anticorrosion component and micro-analysis of hydration products of fly ash and slag on the influence of the nitrites corrosion inhibition was studied by the free nitrite ion concentration and X-ray diffraction pattern. The free nitrite ion concentration was used to describe the corrosion inhibition effect of nitrites. And the X-ray diffraction patterns were used to analyze the adsorption properties. The research results show that fly ash and slag were beneficial for improving the corrosion inhibition effect of nitrites. Cement-based materials with slag at low content presented high free nitrite ion concentration, but the addition of low content of fly ash harmed the corrosion inhibition effect of nitrites. The specimens incorporated with both fly ash and slag can reach the highest free nitrite ion concentration when the compounding proportion was 1:1. It was concluded that the extent of mineral admixtures of the corrosion inhibition effect of nitrites was affected by its type and content.

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Research Progress of Carrier-Free Antitumor Nanoparticles Based on Phytochemicals

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.799806 ◽

2021 ◽

Vol 9 ◽

Author(s):

Siliang Jiang ◽

Yu Fu ◽

Xinyang Zhang ◽

Tong Yu ◽

Bowen Lu ◽

...

Keyword(s):

Public Health ◽

Research Progress ◽

Public Health Issue ◽

Lifestyle Behaviors ◽

Increase Cancer Risk ◽

Traditional Treatment ◽

Acquired Drug Resistance ◽

Nanodrug Delivery ◽

Carrier Free

Cancer is a major worldwide public health issue, responsible for millions of deaths every year. Cancer cases and deaths are expected to increase rapidly with population growth, age, and lifestyle behaviors that increase cancer risk. Long-term chemotherapy results in acquired drug resistance. Traditional treatment methods have limitations and cannot effectively treat distal metastatic cancers. Application of nanocarriers in multi-chemotherapy must be promoted. With research progress, the shortcomings of traditional nanocarriers have gradually become evident. Carrier-free nanodrugs with desirable bioactivity have attracted considerable attention. In this review, we provide an overview of recent reports on several carrier-free nanodrug delivery systems based on phytochemicals. This review focuses on the advantages of carrier-free nanodrugs, and provides new insights for establishment of ideal cancer treatment nanosystems.

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Phosphorus Removal from Manure by Mechanical Separation using Salt and Polymers: Theoretical Simulations and Experimental Data

Applied Engineering in Agriculture ◽

10.13031/aea.13726 ◽

2020 ◽

Vol 36 (2) ◽

pp. 175-185

Author(s):

Morten Lykkegaard Christensen ◽

Kristian Keiding ◽

Peter Vittrup Christensen

Keyword(s):

Calcium Phosphate ◽

Chemical Equilibrium ◽

Phosphorus Removal ◽

Solid Material ◽

Ion Concentration ◽

Iron Sulfate ◽

Molar Ratio ◽

Pig Manure ◽

Polymer Addition ◽

The Stability

Abstract.Full-scale separation apparatuses were used to process mink and sow manure. Mink manure was pretreated with iron sulfate and polymer; pig manure was pretreated with only polymer. Testing was done to study how adding chemicals affected phosphorus removal. Chemical equilibrium simulations show that raw manure contains several minerals, i.e., struvite, calcium phosphate, and vivianite. The estimated mass of struvite fit well with the amount of magnesium measured in the solid material. The amount of calcium phosphate precipitation depended on the stability constant of the complexes of organic material and calcium ions, estimated at pK = 3.5–4. With polymer addition, it was possible to remove mineral-bound phosphorus but not organic-bound phosphorus and orthophosphate. With iron salt addition, it was possible to remove both phosphorus minerals and dissolved orthophosphate. The molar ratio between orthophosphate and iron ions in the precipitate was measured to be 2:3. These data fit well with the chemical equilibrium simulations, which predicted that vivianite would form when the iron ion concentration increased. The simulation also indicated that the amount of struvite decreased slightly with iron addition. Keywords: Coagulation, Flocculation, Solid-liquid separation, Vivianite, Wastewater.

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The Research Progress of Heavy Metals in PM2.5

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.1397 ◽

2014 ◽

Vol 955-959 ◽

pp. 1397-1404 ◽

Cited By ~ 2

Author(s):

Li Na Shi ◽

Xun Xu ◽

Xiao Yan Dou ◽

Xu Dong Zhao

Keyword(s):

Heavy Metals ◽

Air Pollution ◽

Human Health ◽

Human Body ◽

Chemical Form ◽

The Body ◽

Detection Methods ◽

Research Progress ◽

Depth Study

PM2.5 is one of the most important components in air pollution. It is also the focus of the most closely watched at home and abroad. Based on its small size, complex components, and strongenvironmental activity, it can be used as a carrier for chemicals, heavy metals, bacteria, toxins and carcinogens into the body. Then, as a result, it will affect Human Body Health. Heavy metals are important components of PM2.5, and the long-term accumulation of heavy metals in PM2.5 poses a great threat on human health and the environment. This paper reviewed the sources, distribution methods,chemical form, detection methods, disposal way, research progress of heavy metals in PM2.5. As a result, it provided a reference for in-depth study on the future.

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Mobility of Ra-226 and Heavy Metals (U, Th and Pb) From Pyritic Uranium Mine Tailings Under Sub-Aqueous Disposal Conditions

ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B ◽

10.1115/icem2011-59283 ◽

2011 ◽

Author(s):

Nand K. Dave´

Keyword(s):

Heavy Metals ◽

Surface Water ◽

Mine Tailings ◽

Ion Concentration ◽

Uranium Mine ◽

Acid Generation ◽

Shallow Zone ◽

Acidic Conditions ◽

Waste Repositories

Laboratory lysimeter studies were undertaken to evaluate the leaching characteristics and mobility of Ra-226 and other heavy metals (U, Th and Pb) from pyritic uranium mine tailings under sub-aqueous disposal conditions for assessing the long-term radiological stability of such waste repositories. The experiments were conducted using three types of un-oxidized tailings: fine, coarse and gypsum depleted mill total tailings. The results showed that Ra-226 was leached from surface of the submerged tailings and released to both surface water and shallow zone pore water during initial low sulphate ion concentration of the surface water cover in all three cases. The release of Ra-226 was further enhanced with the onset of weak acidic conditions in the surface water covers of both coarse and gypsum depleted mill total tailings. With additional acid generation and increasing sulphate and iron concentrations, the dissolved Ra-226 concentrations in the water covers of these tailings gradually decreased back to low levels. Pb was also leached and mobilized with the development of moderate acidic conditions at the surface of the submerged coarse and gypsum deplete tailings. No leaching of U and Th was observed.

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Behavior of PMMA Denture Base Materials Containing Titanium Dioxide Nanoparticles: A Literature Review

International Journal of Biomaterials ◽

10.1155/2019/6190610 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14 ◽

Cited By ~ 14

Author(s):

Mohammed M. Gad ◽

Reem Abualsaud

Keyword(s):

Titanium Dioxide ◽

Clinical Performance ◽

Titanium Dioxide Nanoparticles ◽

Antimicrobial Effect ◽

Research Progress ◽

Resin Matrix ◽

Denture Base ◽

Base Materials ◽

Pmma Resin

Titanium dioxide nanoparticles (TiO2NP) have gained interest in the dental field because of their multiple uses in addition to their antimicrobial effect. One of the applications in dentistry involves the incorporation into poly methyl methacrylate (PMMA) resin. However, there is a lack of evidence on their effects on the behavior of the resulting nanocomposite. Therefore, the present review aims to screen literatures for data related to PMMA/TiO2nanocomposite to figure out the properties of TiO2nanoparticles, methods of addition, interaction with PMMA resin matrix, and finally the addition effects on the properties of introduced nanocomposite and evidence on its clinical performance. Regardless of the latest research progress of PMMA/TiO2nanocomposite, the questionable properties of final nanocomposite and the lack of long-term clinical evidence addressing their performance restrict their wide clinical use. A conclusive connection between nanoparticle size or addition method and nanocomposite properties could not be established.

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Review of Estimating Trophic Relationships by Quantitative Fatty Acid Signature Analysis

Journal of Marine Science and Engineering ◽

10.3390/jmse8121030 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1030

Author(s):

Junbo Zhang ◽

Chonglan Ren ◽

Hu Zhang ◽

Fang Yin ◽

Shuo Zhang ◽

...

Keyword(s):

Fatty Acid ◽

First Generation ◽

Trophic Relationships ◽

Research Progress ◽

Signature Analysis ◽

Fatty Acid Signature ◽

Predator Prey ◽

Quantitative Ecology ◽

Improper Use

The dynamic predator–prey relations in the food web are vital for understanding the function and structure of ecosystems. Dietary estimation is a research hotspot of quantitative ecology, providing key insights into predator–prey relationships. One of the most promising approaches is quantitative fatty acid signature analysis (QFASA), which is the first generation of statistical tools to estimate the quantitative trophic predator–prey relationships by comparing the fatty acid (FA) signatures among predators and their prey. QFASA has been continuously widely applied, refined and extended since its introduction. This article reviewed the research progress of QFASA from development and application. QFASA reflects the long-term diet of predator, and provides the quantitative dietary composition of predator, but it is sensitive to the metabolism of predator. The calibration coefficients (CCs) and the FA subset are two crucial parameters to explain the metabolism of predators, but the incorrect construction or improper use of CCs and the FA subset may cause bias in dietary estimation. Further study and refinement of the QFASA approach is needed to identify recommendations for which CCs and subsets of FA work best for different taxa and systems.

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