Ashok Kumar Kumar Malik

Dr. Ashok Kumar Kumar Malik


Research Focus & Metrics

Academic Career Length

35Years (1992-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 July 2003 in Journal of Environmental Monitoring
Verified
Journal Article
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VSVaneet Kumar Sharma
Vaneet Kumar Sharma
JAJ. S. Aulakh
J. S. Aulakh
AMAshok Kumar Kumar Malik
Ashok Kumar Kumar Malik
In this review a brief introduction to thiram (tetramethylthiuram disulfide; TMTD) pesticide has been given along with other applications. All the important methods available are systematically arranged and are listed under various techniques. Some of these methods have been applied for the determination of thiram in commercial formulations, synthetic mixtures in grains, vegetables and fruits. A comparison of different methods is the salient feature of this review.

1 September 2014 in Journal of Chromatography A
Verified
Journal Article
Closed access
RKRajesh Kumar
Rajesh Kumar
GAGaurav
Gaurav
HEHeena
Heena
AMAshok Kumar Kumar Malik
Ashok Kumar Kumar Malik
Abuzar KabirAbuzar Kabir
Abuzar Kabir
KFKenneth G. Furton
Kenneth G. Furton


23 June 2017 in Critical Reviews in Analytical Chemistry
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Journal Article
Closed access
HRHeena Rekhi
Heena Rekhi
SRSusheela Rani
Susheela Rani
NSNeha Sharma
Neha Sharma
AMAshok Kumar Kumar Malik
Ashok Kumar Kumar Malik
High-performance liquid chromatography (HPLC) has several advantages over the conventional methods due to their operational simplicity. It is a vital tool to determine metal ions having same mass but different electronic configuration, to separate complex mixtures and to resolve ions that may be indistinguishable by mass spectrometry alone. Metal ions play vital role in many biological processes and involved in setting up of many diseases. Therefore, the development of simple methods for the detection and quantification of metals in real samples might serve as diagnostic tools for various diseases. This review article focuses on the recent main feature of this technique, i.e. speciation of metal ions and their applications to series of problem of metal ion chemistry in different environmental matrixes. Speciation of metals is of increasing interest and has a great importance because of bioavailability, environmental mobility, toxicity and potential risk of metals. With the capability of partitioning the complex species of different metal ions, HPLC is an efficient technique for this task. This review summarizes recent advances in the development of HPLC to the fundamental understanding of metal ion chemistry in the environment and discusses all the issues that still need a lot of consideration. It has been classified into different sections depending on the role of HPLC in separation used and metal speciation; furthermore, the underlying sample preconcentration techniques and detection systems involved for the determination of metal ions and their applications were discussed.

1 November 2008 in Analytica Chimica Acta
Verified
Journal Article
Closed access
AKAshwini Kumar
Ashwini Kumar
AMAshok Kumar Kumar Malik
Ashok Kumar Kumar Malik
DTDhananjay Kumar Tewary
Dhananjay Kumar Tewary

17 February 2006 in Journal of Separation Science
Verified
Journal Article
Open access
PDF file
VKVarinder Kaur
Varinder Kaur
AMAshok Kumar Kumar Malik
Ashok Kumar Kumar Malik
NVNeelam Verma
Neelam Verma
This paper reviews recent developments of solid phase microextraction (SPME) and its application to the analysis of organometallic species of lead, arsenic, mercury, tin, and selenium by hyphenation with HPLC‐GC‐atomic spectrometry. In the first part, a background of the technique is given in terms of derivatization, fibers used, extraction and desorption conditions. The second part summarizes typical SPME applications to the determination of organometallic species and the main experimental conditions with the aid of specific examples. Most of the applications comprise alkylation with NaBEt4 and headspace extraction followed by gas chromatographic separation with a suitable detector.