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Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM, Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 'Energy Storage and Conversion based on Hydrogen' of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group 'Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage'. The following topics are covered by the review: multiscale modelling of hydrides and hydrogen sorption mechanisms; synthesis and processing techniques; catalysts for hydrogen sorption in Mg; Mg-based nanostructures and new compounds; hydrides based on intermetallic TiFe alloys, high entropy alloys, Laves phases, and Pd-containing alloys. Finally, an outlook is presented on current worldwide investments and future research directions for hydrogen-based energy storage

Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 'Energy Storage and Conversion based on Hydrogen' of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group 'Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage'. The following topics are covered by the review: multiscale modelling of hydrides and hydrogen sorption mechanisms; synthesis and processing techniques; catalysts for hydrogen sorption in Mg; Mg-based nanostructures and new compounds; hydrides based on intermetallic TiFe alloys, high entropy alloys, Laves phases, and Pd-containing alloys. Finally, an outlook is presented on current worldwide investments and future research directions for hydrogen-based energy storage.

The crisis of energy has become the main concern for human civilization. Microalgae is an attractive source of biomass for energy production because it has high productivity, does not compete with food, do not require a large area and its ability to absorb CO2. Chlorella sp. has the potential to be used as raw material for biodiesel due an oil content of 28-32% and easily developed in Indonesia. Harvesting is a very cost-determining step in converting algal biomass into biodiesel. Cationic starch has a strong potential as a flocculant agent because of its abundance and low price. This research aims to identify the potential of cation starch as a flocculant agent and obtain optimum the condition for harvesting Chlorella sp. Based on this study, cationic starch can be used as an alternative organic flocculant for Chlorella sp. The optimum dose and flocculation are 1 g/L dosage, 400 rpm flocculation speed and 15 minute flocculation time. With the optimum condition, harvesting efficiency on the laboratory scale is 98.23% and the pilot scale is 96.05%. This difference in harvesting efficiency values indicates that the efficiency tends to decrease with a larger volume of Chlorella sp.

Rice bran oil (RBO) is a healthy vegetable oil made from rice bran. A microwave- assisted extraction method (MAE) was developed in this work to produce RBO with greater productivity than the conventional method, i.e., solvent extraction (SXE). Furthermore, green solvents such as ethanol and d-limonene were compared as an alternative to the less environmentally friendly n-hexane. An evaluation of energy consumption and raw material costs was conducted using the MAE method. The 30 mesh bran was stabilized in the oven for 30 min at 100°C followed by MAE extraction, which was performed by mixing 50 g of bran and 300 ml of solvents in a microwave oven set to 450 watts and 60°C for 60 min. Filter paper was used to separate the extract from the bran, and the oil was recovered by solvent evaporation. Finally, the oil was weighed and the fatty acid composition was determined by GC-MS. The results showed that the yield of RBO using d-limonene and MAE was the largest (24.64%) as well as consuming less energy (95Wh/gr oil). Linoleic acid was only found in the extraction with d-limonene and EtOH was successful in obtaining longer-chain saturated fatty acids.

This study aims to analyze the plankton community in the sea waters around Panjnag and Pamujan Besar Islands. It was conducted for three months, from May to July 2019, at six locations around the islands. Analysis was carried out to estimate abundance and the diversity, evenness, and dominance indices. Based on the study, the observed phytoplankton consisted of 3 classes, i.e., Bacillariophyceae (30 genera), Cyanophyceae (2 genera), and Dinophyceae (5 genera). The most abundant genera were Chaetoceros sp, Spirulina sp and Rhizosolenia sp. Meanwhile, the zooplankton consisted of 8 classes, i.e., Bivalvia, Ciliata (6 genera), Malacostraca (13 genera), Gastropods, Polychaeta, Sarcodina (1 genus), Rotifera (1 genus), and Urochordata (1 genus), with Nauplius, Calanus, and Bivalve larvae as the most abundant biota. The abundance of phytoplankton and zooplankton varied, 38095-13038515 cells/m3 (phyto) and 4010-190475 inds./m3 (zoo), respectively. The diversity, evenness and dominance indices of the phytoplankton and zooplankton were 0.693-2.146, 0.694-1.00, 0.160-0.341, and 0.780-2.027, 0.275-0.861, 0.160-0.500, respectively. Based on the results, the diversity value is moderate with high evenness and no dominant genera.

The sea waters around Panjang and Pamujan Besar Islands (Banten Bay) are fishing grounds and recreation areas for local communities around the bay. The research activity on the macrozoobenthos community structure was carried out from May to July 2019 at 6 stations scattered around the islands. This study evaluates the macrozoobenthos community structure at the sea waters around these islands. Data analysis was carried out on density, diversity, evenness, and dominance indices. Based on the research results, there were 23 genera of the macrozoobenthos from four classes, namely Bivalvia (2 genera), Gastropoda (7 genera), Malacostraca (7 genera), and Polychaeta (7 genera). Pronospio sp., Nephthys sp., and Nereis sp. were the most common genera of macrozoobenthos found at each station. Based on the calculation results, the density varied between 58 and 406 ind/m2. The value of the diversity, evenness, and dominance indices at each station ranged between 1.00 and 2.842, 0.935 to 1.00, and 0.157 to 1.00, respectively. Based on these values, the sea water condition in Panjang and Pamujan Besar Islands has medium diversity, high evenness, and no dominant macrozoobenthos.

Although coal mining activities have an Environmental impact assessment EIA/Amdal, these activities still pose serious risks to communities in rural Indonesia. This study links EIA/Amdal with the social context of a risk society. This study aims to evaluate the legitimacy of Amdal for coal mining in Indonesia. The legitimacy of the Amdal for coal mining is based on the beliefs of experts, science, and technology (Rational model). The survey and interviews involved stakeholders in 6 coal mining villages and the Indonesian Mining Experts Association (PERHAPI). The results show that rural stakeholders are increasingly distrustful of Amdal (rational model) in avoiding risk. Meanwhile, mining expert groups still rely on rational models in making environmental decisions.

A pilot plant scale of SFE (steam flash explosion) chamber has been developed in order to process raw grobogan soybean. The objectives of this research were to study the physicochemical changes of soybean in term of reaction kinetics approach and to determine the optimal variables to produce high quality soybean. We used 2.5 kg and 5 kg of soybean, representing 75% and 50%, respectively, of headspace volume of SFE chamber. After soaking in the water, these soybeans were then treated using SFE chamber operated at temperature of 115 °C (P=1 bar), 125 °C (P=2 bar), and 135 °C (P=3 bar) and time interval of 0, 5, 10, 15, 20, and 25 minutes, after which the steam was suddenly released from the chamber to provide explosion effect. The treated soybean samples were then analyzed for hardness, color characteristics, urease index (UI), protein dispersibility index (PDI), and protein solubility index (PSI). The result showed that the decrease of hardness and b-value (yellowness) of soybean during processing can be explained by 1st order kinetic model. As for hardness, SFE gave kT=115°C=0.0344 minutes-1, kT=125°C=0.0495 minutes-1, kT=135°C=0.0864 minutes-1, and Ea=60.350 Kj.mol-1 (for 2.5 kg capacity); and kT=115°C=0.0314 minutes-1, kT=125°C=0.0442 minutes-1, and kT=135°C=0.0858 minutes-1, and Ea=66.009 Kj.mol-1 (for 5 kg capacity). As for b-value, SFE gave kT=115°C=0.0225 minutes-1, kT=125°C=0.0378 minutes-1, kT=135°C=0.0558 minutes-1, and Ea=59.873 Kj.mol-1 (for 2.5 kg capacity); and kT=115°C=0.0258 minutes-1, kT=125°C=0.0393 minutes-1, kT=135°C=0.0553 minutes-1, and Ea=64.544 Kj.mol-1 (for 5 kg capacity). The Ea for 5 kg capacity is higher than Ea for 2.5 kg capacity. This research found no appropriate reaction kinetics model for urease index, PSI, dan PDI. Soybean treated under 115 °C (1 bar) within 5 minutes for both capacities satisfy the processed soybean quality requiement.

The Ciliwung River receives loads from various sources of pollution along the border, both from agricultural waste, industrial waste, and domestic waste. The various wastes that enter the river cause a decrease in water quality. This study aims to determine the water quality status of the Ciliwung River in the Jakarta segment based on the Pollution Index (PI) and the Pesce-Wunderlin Water Quality Index (WQI). Monitoring on Ciliwung River water quality in the Jakarta segment was carried out in February-September 2021 at 18 observation stations. Most of the parameter tested for the water quality of the Ciliwung River in Jakarta does not meet the river water quality standards of class II based on Attachment VI of Government Regulation of the Republic of Indonesia Number 22 of 2021, such as total suspended solid, total dissolved solid, dissolved oxygen, ammonia, nitrite, total nitrogen, biochemical oxygen demand, chemical oxygen demand, total coliforms, and fecal coliforms. The water quality status of the Ciliwung River in the Jakarta segment is in medium to bad condition based on the Pesce-Wunderlin Water Quality Index and classified as moderately to extremely polluted based on the Pollution Index.

White pepper (Piper nigrum L.) is a spice with earthy heat and an intense floral aroma widely produced and consumed in Asia. In Indonesia, it is commonly used to flavor dishes that require a spicy taste. However, white pepper can be contaminated by pathogenic microorganisms, such as Bacillus cereus, an endospore-forming bacterium widely grounded in soil and dust. The bacterium causes emetic and diarrheal syndromes and has been implicated in various foodborne disease outbreaks in different parts of the world. Currently, data pertaining to the occurrence of Bacillus cereus in white pepper in Indonesia is not available. This study aimed to isolate and assess the occurrence of Bacillus cereus in white pepper obtained from markets in Bogor, Indonesia. The study consisted of sample collection and preparation, isolation and enumeration of Bacillus cereus using Mannitol egg yolk polymyxin (MYP) agar, and confirmation by biochemical tests and Polymerase Chain Reaction to detect the gene encoding for16S rRNA. Of the 20 samples analyzed, 18 of them (90%) were contaminated with presumptive Bacillus cereus, and the highest concentration was 5.77 log10 cfu/g. The high counts of Bacillus cereus were probably attributed to the postharvest processing operations that the spice encountered. All the 15 tested isolates showed a clear band at the expected length of around 1686bp after being separated from PCR products on ethidium bromide-stained 2% agarose gel. This result confirmed the existence of Bacillus cereus in white pepper samples.

Plastic pollution in an aquatic ecosystem may negatively impact ecology, aquatic species, and causes economic damage. Rivers provide an excellent opportunity for intercepting plastic pollution before it reaches the ocean. The aim of this study is to identify and quantify the number of plastic debris in the Citarum River. Plastic debris was collected from April to August 2021 at three sampling sites based on the stream location, i.e. upstream, midstream, downstream, using a framed pocket net with 1cm-mesh size as a sampler with the dimension of 2x1x3 meter that was installed at two transversal locations of the river. Observation was conducted three times a day, morning, noon, and afternoon each with 15-30 minutes duration. The methods applied include plastic debris separation, enumeration, classification, volume estimation, and weighting. Type of plastics that are commonly found in high number of items are plastic bags, clear plastic bags, and plastic packaging. The highest volume of plastic debris was found in the upstream part of the Citarum River compared to midstream and downstream. The existing reservoirs act as a trap for plastic debris and all riverine debris of the Citarum River. The plastic debris tends to be higher in the morning than noon or afternoon.

The Citarum River, Indonesia, has undergone degradation due to the pollutants, including phosphorus, that enters the river and the reservoirs of Saguling, Cirata, and Juanda (The official name of Jatiluhur Reservoir). The observations of total phosphorus (TP) load instantaneously had been carried out on the three reservoirs and TP measurements from 8 to 12 August 2019. The TP concentration in the inlets was generally very high (> 0.3 mg L-1), whereas the average TP concentration in Saguling, Cirata, and Juanda Reservoirs was 0.378 mg L-1, 0.343 mg L-1, and 0.324 mg L-1, respectively. Based on the trophic criteria, the condition of the waters in the three reservoirs was hypertrophic. Meanwhile, the average TP level in the Saguling showed the highest level compared to other reservoirs, which is in line with the TP concentration that enters the Saguling Reservoir, which is generally very high. Based on the instantaneous inputs, the loading TP to Saguling, Cirata, and Juanda Reservoirs were 26.471 g sec-1, 36.241 g sec-1, and 55.573 g sec-1, respectively. This indicates that the loading of phosphorus from upstream to downstream tends to increase.

Concrete is a building material that is widely used in the construction industry. With the increasing need for concrete, the demand for constituent materials will increase. To reduce dependence on natural materials, the recycling process of the concrete waste has been encouraged recently. This study applied a heating and grinding method of waste concrete to obtain higher quality recycled coarse aggregate. The addition of vibrations in the mixing process is aimed to enhance the recycled concrete compressive strength. To produce recycled coarse aggregate, the concrete waste was heated to a temperature of 100°C for 24 hours followed by a grinding process using a Los Angeles machine for 600 cycles. Additional vibrations for 30, 60, and 90 were applied in a concrete mixer during the mixing process. Conventional concrete with normal aggregate and no additional vibration during mixing was also provided for comparison. According to the experimental results, the quality of natural coarse aggregate and the recycled one using heating and grinding methods is not much different. Compressive strength of recycled aggregate concrete with vibrations of 30, 60, and 90 seconds increases 21.1%, 22.1%, and 22.6% sequentially correlated to normal concrete. Recycled concrete using heating and grinding methods with the addition of vibration during the mixing process is effective to be used as an alternative to normal coarse aggregate.

Indonesia’s geographical location as an archipelago makes this country has a humid tropical climate. This climate will affect asthmatics. Asthma attacks a patient suddenly, this is very dangerous especially if the patient is a child. Before attacking usually, asthma will react to the body with the characteristics of changes in breathing frequency, pulse frequency, mild, severe, even to the point of stopping breathing. Asthma attacks will be very dangerous for children who are not under the supervision of their parents (being in school for example). It can be imagined if asthma with severe clusters aims. The purpose of this study is to propose the design of wearable-type devices used in children at home to facilitate monitoring of asthma attacks through the internet network.