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Fulltext A review of the mechanism and role of wax inhibitors in the wax deposition and precipitation

Hao, Lim Zhen, Hikmat Said Al-Salim, Norida Ridzuan

Pertanika Journal of Science & Technology, 2019;27(1):499-526.
MyJurnal

The continuous depletion of global oil reserves with the propensity for light distillates
propels the oil and gas industry to explore heavier fractions of crude oils with significant
amount of paraffin waxes. However, the precipitation and deposition of waxes during the
transportation of these waxy crude oils in the pipelines contribute to several issues, such as
the flowability reduction, excessive pumping cost, and wax gel formation, that adversely
affect the supposedly steady offshore oil production. As a result, substantial resources are
expended to resolve these flow assurance problems. The wax inhibitors and pour point
depressants are developed and modified to meet the wax remediation criteria. Essentially,
the wax crystals are formed through the nucleation, growth, and agglomeration processes,
while the deposition of these waxes occurs via molecular diffusion and shear dispersion.
The wax inhibitors are able to control the growth of wax crystals through nucleation, cocrystallization,
adsorption, and dispersion interactions. This paper particularly assessed
the following compounds: (1) polymeric wax inhibitors, (2) nano-hybrid pour point
depressants, (3) organic solvents, and
(4) surfactants. Given the significance of
these compounds in the deposition and
precipitation of waxes, it is imperative to
comprehensively explore the types and
nature of these compounds and their recent
applications as well as to critically assess
their strengths and drawbacks, which were
addressed in this paper. Furthermore, the
challenges of using these compounds and the factors that govern their efficiencies were also discussed. Accordingly, the carbon
length and the molecular weight of both paraffin waxes and wax inhibitors are among the
most influential factors.
Fulltext Investigation on the Suitability of Natural Gas Hydrate Formation Prediction Simulation Packages and its Implementation Conditions

Firas Basim Ismail Alnaimi, Chee Liang Lim Henry, Amar Sahed, Hikmat S. Al Salim, Mohammad Shakir Nasif

Pertanika Journal of Science & Technology, 2020;28(101):0-0.
MyJurnal

In natural gas processing, carbon dioxide is one of the major streams contaminate from the gas reservoir and must be removed, as it reduces the energy content of sales gas. In order to remove huge amounts of carbon dioxide (CO2), gas hydrate is used to capture CO2. However, the high formation of hydrate will inhibit clogs in gas pipelines. Hence, this research presents literature on hydrate formation, prediction of methane-carbon dioxide (CH4-CO2) gas mixture, by using simulation packages of Aspen Hysys 7.2, K-factor, VMG SIM Ver. 6 and BR & E ProMax 2.0. Peng-Robinson model was used in all simulation packages. Simulation results obtained were then compared with experimental data from previous literature sources. The simulation results showed that the higher the concentration of CO2 in CH4-CO2 gas mixture, the lower the pressure required for CO2 hydrate to form throughout the predicted temperature range from -20°C to 20°C.
Exploring community nurses' perspectives on adolescent suicide prevention in Indonesia: A descriptive qualitative study

Yosep I, Mardhiyah A, Hikmat R, Hazmi H, Abdillah H, Tumanggor RD, et al.

Acta Psychol (Amst), 2026 Oct 31;271:108060.
PMID: 42966062 DOI: 10.1016/j.actpsy.2026.108060

BACKGROUND: Adolescent suicide prevention is not only a clinical or service-delivery problem; it is also socially organized through stigma, family and community norms, trust, help-seeking expectations, and the relationships that connect adolescents with potential helpers. In Indonesia, community nurses work at the interface of adolescents, families, schools, primary health care, and community institutions, yet little is known about how they interpret and negotiate this role.
PURPOSE: To explore community nurses' perspectives on adolescent suicide prevention in Indonesia, focusing on how suicide risk becomes visible or remains hidden, how nurses understand their preventive roles, the barriers that constrain action, and the support and system conditions needed to strengthen practice.
METHOD: A descriptive qualitative study was conducted in Bandung, West Java, Indonesia with 14 purposively selected community nurses. Individual semi-structured interviews were analyzed using a codebook-oriented thematic analysis. Reporting was guided by the Consolidated Criteria for Reporting Qualitative Research (COREQ).
RESULTS: Four interpretative themes were developed: suicide risk is socially hidden before it becomes clinically visible; community nurses function as relational gatekeepers whose effectiveness depends on trust; normative stigma and professional uncertainty constrain preventive action; and nurses are expected to coordinate across sectors without sufficient structural enablement. Participants described shame, fear of judgment, family responses, and religious or moral sensitivities as shaping disclosure and help-seeking. They also described roles in mental health education, early recognition, supportive communication, family engagement, and referral, while emphasizing limited suicide-specific training, unclear pathways, and fragmented school-family-health service coordination.
CONCLUSIONS: Community nurses occupy a potentially important social-psychological and service-system position in adolescent suicide prevention in Indonesia. Their effectiveness depends not only on individual knowledge but also on the social conditions that make disclosure safe and help-seeking legitimate, together with clear protocols, referral pathways, cross-sector collaboration, and institutional support within existing Indonesian adolescent and primary-care platforms.
Deposition and characterization of SnSe and CuInSe2 thin films by thermal evaporation technique from synthesized SnSe and CuInSe2 sources

Nordin Sabli, Zainal Abidin Talib, Chang CB, Wan Mahmood Mat Yunus, Zulkarnain Zainal, Hikmat S. Hilal, et al.

Sains Malaysiana, 2014;43:1061-1067.

Tin selenide (SnSe) and copper indium diselenide (CuInSe2) compounds were synthesized by high temperature reaction method using combination of sealed ampoule (at relatively low pressure ~10-1 Pa without inert gas) and heating at specific temperature profile in rocking furnace. Powder X-Ray diffraction analysis showed that the products involved only single phases of SnSe and of CuInSe2 only. Using the reaction products as source materials, the SnSe and CuInSe2 thin films were vacuum-deposited on glass substrates at room temperature. Structural, elemental, surface morphological and optical properties of the as-deposited films were studied by X-Ray diffraction (XRD), energy dispersive X-Ray (EDX) analysis, field emission scanning electron microscopy (FESEM) and UV-Vis-NIR spectroscopy. Single phase of SnSe and CuInSe2 films were obtained by thermal evaporation technique from synthesized SnSe and CuInSe2 compound without further treatment.
Microplastic contamination in the Skipjack Tuna (Euthynnus affinis) collected from Southern Coast of Java, Indonesia

Andreas, Hadibarata T, Sathishkumar P, Prasetia H, Hikmat, Pusfitasari ED, et al.

Chemosphere, 2021 Aug;276:130185.
PMID: 33743420 DOI: 10.1016/j.chemosphere.2021.130185

Indonesia is the second-largest contributor of microplastics (MPs) pollution in the marine ecosystem. Most MPs pollution-related studies in Indonesia focus on seawater, sediment, with less information found on the commercially important fish species used for human consumption. Skipjack Tuna (Euthynnus affinis) is one of the major exporting fishery commodities from Indonesia. This exploratory study aimed to determine MPs presence in the digestive tract of Skipjack Tuna from the Southern Coast of Java, Indonesia. The fish samples were collected from five different fish traditional auction market along the Southern Coast of Java, Indonesia, namely Pangandaran, Pamayang Sari, Ciletuh, Santolo, and Palabuhan Ratu. The gastrointestinal tract of Skipjack tuna was pretreated using alkaline destruction and filtered. The presence of MPs in the treated samples was visually identified using an optical microscope, while Polybrominated diphenyl ethers (PBDEs) contaminants were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). A total of 19 suspected MPs particles were found in the form of filament (84%), angular (11%), and round (5%). This result would provide a better indication of the MPs contamination in marine life species in the Southern Coast of Java, Indonesia, as useful information for marine environmental monitoring program in the future.
Fulltext Progressive deafness-dystonia due to SERAC1 mutations: A study of 67 cases

Maas RR, Iwanicka-Pronicka K, Kalkan Ucar S, Alhaddad B, AlSayed M, Al-Owain MA, et al.

Ann Neurol, 2017 Dec;82(6):1004-1015.
PMID: 29205472 DOI: 10.1002/ana.25110

OBJECTIVE: 3-Methylglutaconic aciduria, dystonia-deafness, hepatopathy, encephalopathy, Leigh-like syndrome (MEGDHEL) syndrome is caused by biallelic variants in SERAC1.
METHODS: This multicenter study addressed the course of disease for each organ system. Metabolic, neuroradiological, and genetic findings are reported.
RESULTS: Sixty-seven individuals (39 previously unreported) from 59 families were included (age range = 5 days-33.4 years, median age = 9 years). A total of 41 different SERAC1 variants were identified, including 20 that have not been reported before. With the exception of 2 families with a milder phenotype, all affected individuals showed a strikingly homogeneous phenotype and time course. Severe, reversible neonatal liver dysfunction and hypoglycemia were seen in >40% of all cases. Starting at a median age of 6 months, muscular hypotonia (91%) was seen, followed by progressive spasticity (82%, median onset = 15 months) and dystonia (82%, 18 months). The majority of affected individuals never learned to walk (68%). Seventy-nine percent suffered hearing loss, 58% never learned to speak, and nearly all had significant intellectual disability (88%). Magnetic resonance imaging features were accordingly homogenous, with bilateral basal ganglia involvement (98%); the characteristic "putaminal eye" was seen in 53%. The urinary marker 3-methylglutaconic aciduria was present in virtually all patients (98%). Supportive treatment focused on spasticity and drooling, and was effective in the individuals treated; hearing aids or cochlear implants did not improve communication skills.
INTERPRETATION: MEGDHEL syndrome is a progressive deafness-dystonia syndrome with frequent and reversible neonatal liver involvement and a strikingly homogenous course of disease. Ann Neurol 2017;82:1004-1015.