STABILITY ENHANCEMENT OF ALUMINUM-AIR BATTERY

A comparative analysis is presented for an aluminum-air battery with a carbon-coated and non-coated anode made of 4N pure aluminum with the purpose to enhance the stability of the battery. The carbon coating was proven to be quite effective which lasted almost two times more than the non-coated cell with little to almost no effect on the electrochemical behavior. A method was also proposed to limit the self-discharge electrode corrosion of the aluminum-air battery by limiting the oxygen supply to the cell from atmospheric air. The blockage of the air supply limits the oxidation-reduction reaction necessary for cell operation. For that purpose, the cell was tested in vacuum condition for 25 days which showed quite impressive results when compared with the cell kept in a non-vacuum room condition. It had retained its potential as well as resisted the corrosion quite well with almost negligible weight loss and byproduct accumulation

Increasing workers comfort: experiment of the effect of color and lighting in assembly manufacture

Color and light are the main factors in the car manufacturing industry, with not much research, conducted on this topic, related to employee physical comfort. The factor affecting employee work comfort is the color factor and lighting time in their workplace environment. Color is the light, reflected by an object, then interpreted by the eye based on the light that hits the object. The value of the color wavelength in the spectrum of 380 nm to780 nm impacts worker performance. Good lighting will affect whether or not the room’s light conditions affect the illumination’s value. A good working room condition will affect the physical comfort of employees. Employee physical comfort has developed in many previous studies. However, research on the configuration of colors and lighting in the manufacturing industry’s work environment is still underdeveloped. This research aims to measure and determine the impact of color and lighting at specific color wavelengths on the illumination value and the employee’s physical comfort. It starts with studying the color, light, human comfort, then examines the effect on the manufacturing industry employees’ performance in the wiring installation assembly industry. Color and light settings are proven essential to get better human comfort. Green color with a wavelength of 490 nm to 570 can increase the highest illuminate average lux value of 12.43 %. Yellow can increase the heart rate by 4.85 %, while green can reduce Diastole by 2.95 % and Systole by 1.29 %. Pupillary size changes L by 23.17 % and R by 21.43 %. The effect of green color and lighting time can increase the value of illumination and decrease heart rate, blood pressure, and pupil size so that it impacts the physical comfort of employees.

Numerical analysis of cooling potential and indoor thermal comfort with a novel hybrid radiant cooling system in hot and humid climates

The study investigates a hybrid radiant cooling system's potential to achieve thermal comfort. The hybrid radiant cooling (HRC) system combines the best features of a typical all-air and conventional chilled radiant cooling system. An HRC system presents the advantages to (a) reduce vapour condensation and to (b) adjust the cooling output by using an Airbox convector. The three systems perceive thermal comfort in the predicted mean vote (PMV) between –0.5 and +0.5 at 25 and 27°C. In the room condition at 31°C, the all-air system has a lower thermal comfort level because the elevated airspeed is less effective when the mean radiant temperature (MRT) is low. This study suggests a cooling strategy to maximize the thermal comfort level by effectively utilizing the HRC in extreme conditions without extra cooling sources. When the designed set point indoor temperature is 25°C, the Airbox convector of the HRC fan can be off. However, if the indoor air temperature increases above 25°C, an occupant can activate the Airbox convector; the actual thermal output of HRC is increased, and the elevated airspeed can reduce the predicted percentage dissatisfied (PPD) level. Even in an extreme indoor thermal condition at 31°C, the HRC minimizes the PPD level.

Comfortable Room Condition for Working and Resting

This paper aims to determine the comfortable room condition in terms of room organization, lighting and room temperature. Due to the pandemic, many workers are forced to bring their outside home activities back home. Many of them struggle in finding one suitable and comfortable space as they do not have a dedicated space to do the work from home. A bedroom, as one of the potential rooms to maintain the balance between work and rest at home, are observed for space adjustment, especially the organisation of space, lighting and room temperature to maintain the comfort. The comfortable room condition needs to support the bedroom as a working and relaxing space. This study consists of literature review about space, lighting and temperature and observation of two study case studies. This study concludes that the room organization, lighting and room temperature affects the user physically and psychologically which results in the comfort of the user. As a worker, to increase comfort level and have good rest balance, the user needs to adjust the variables of lighting, room temperature and room organization to achieve the optimum comfort level.

Ripening Regulation and Post-harvest Improvement of Banana Cv. Malbhog by Treating with Ethephon

A study entitled “Ripening regulation and post-harvest life improvement of banana Cv. Malbhog using ethephon” was under taken to assess the effect of ethephon on banana fruit ripening and quality parameters after harvest under ordinary room condition. The experiment was conducted at Central laboratory of Post-Harvest Horticulture of Agriculture and Forestry University, Rampur, Chitwan, Nepal in 2016. The experiment was laid out in Completely Randomized Design (CRD) in which the experiment comprised of five treatments; control(no use of ethephon), ethephon @ 250 ppm, ethephon @ 500 ppm, ethephon @ 750 ppm and ethephon @ 1000 ppm replicated four times. On the final day of storage, the maximum physiological loss in weight was observed with ethephon @ 1000 ppm (24.52 %) and the colour score (7.75). Similarly the highest Total Soluble Solids content (19.32ºBrix) was observed with ethephon @ 1000 ppm and the maximum shelf life was found with control (14 days). From the experiment, the use of ethephon @ 1000 ppm and ethephon @ 750 ppm was found more effective regarding banana ripening and other various post harvest parameters and in case, if the bananas are to be stored for long duration, the control treatement is recommended to the farmers because it increases the shelf life.

A comprehensive metagenomics framework to characterize organisms relevant for planetary protection

Background Clean rooms of the Space Assembly Facility (SAF) at the Jet Propulsion Laboratory (JPL) at NASA are the final step of spacecraft cleaning and assembly before launching into space. Clean rooms have stringent methods of air-filtration and cleaning to minimize microbial contamination for exoplanetary research and minimize the risk of human pathogens, but they are not sterile. Clean rooms make a selective environment for microorganisms that tolerate such cleaning methods. Previous studies have attempted to characterize the microbial cargo through sequencing and culture-dependent protocols. However, there is not a standardized metagenomic workflow nor analysis pipeline for spaceflight hardware cleanroom samples to identify microbial contamination. Additionally, current identification methods fail to characterize and profile the risk of low-abundance microorganisms. Results A comprehensive metagenomic framework to characterize microorganisms relevant for planetary protection in multiple cleanroom classifications (from ISO-5 to ISO-8.5) and sample types (surface, filters, and debris collected via vacuum devices) was developed. Fifty-one metagenomic samples from SAF clean rooms were sequenced and analyzed to identify microbes that could potentially survive spaceflight based on their microbial features and whether the microbes expressed any metabolic activity or growth. Additionally, an auxiliary testing was performed to determine the repeatability of our techniques and validate our analyses. We find evidence that JPL clean rooms carry microbes with attributes that may be problematic in space missions for their documented ability to withstand extreme conditions, such as psychrophilia and ability to form biofilms, spore-forming capacity, radiation resistance, and desiccation resistance. Samples from ISO-5 standard had lower microbial diversity than those conforming to ISO-6 or higher filters but still carried a measurable microbial load. Conclusions Although the extensive cleaning processes limit the number of microbes capable of withstanding clean room condition, it is important to quantify thresholds and detect organisms that can inform ongoing Planetary Protection goals, provide a biological baseline for assembly facilities, and guide future mission planning.

Heritage hotels and customer experience: a text mining analysis of online reviews

Purpose In business, online reviews have an economic impact on firm performance. Customers’ data in the form of online reviews was used to understand the appreciation and service complaints written by previous customers. The study is an analysis of the online reviews written by the customers about Indian heritage hotels. This study aims to understand the dimensions of service appreciation and service complaints by comparing positive- and negative-rated reviews and find the patterns in the determinants of the satisfaction and dissatisfaction of the customers. Design/methodology/approach A total of 23,643 online reviews about heritage hotels were collected from the TripAdvisor website by using a Web crawler developed in Python. A total of 1000 reviews were randomly selected for further analysis to eliminate the bandwagon effect. Unsupervised text mining techniques were used to analyze reviews and find out the interesting patterns in text data. Findings Based on Herzberg two-factor theory, this study found satisfied and dissatisfied determinants separately. The study revealed some common categories discussed by satisfied and dissatisfied customers. The factors which satisfy the customers may also dissatisfy the customers if not delivered properly. Satisfied customers mentioned about tangible features of the hotel stay, which includes physical signifiers, traditional services, staff behavior and professionalism and core products (rooms, food). However, most of the customers complained about intangible service problems, such as staff attitude, services failure, issues with reservation and food, value for money and room condition. The results are contradicting with commercial hotels-based studies owing to the unique services provided by heritage hotels. Practical implications The dimensions for satisfaction and dissatisfaction among customer of heritage hotels provide marketers to understand the real emotion and perception of the customers. As these dimensions were extracted through text mining of the reviews written by the customer of heritage hotels, the results would certainly give better insights to the hotel marketers. Originality/value The study is a rare attempt to study online reviews of customers on heritage hotels through a text mining approach and find the patterns in the behavior and the determinants of satisfaction and dissatisfaction of customers.

Synthesis of brightly luminescent colloidal formamidinium lead bromide perovskite FAPbBr3 nanoplatelets with tunable emission

Hybrid halide perovskites are semicondoctor materials with desirable characteristics of color-tunable and narrow-band emissions for lighting and display technology. They have size-tunable emissions due to quantum size effects. In this work, the Formamidinium Lead Bromide perovskite CH(NH2)2PbBr3 nanoplatelets (NPLs) were successfully synthesized by ligand-assisted reprecipitation method under room condition, in which the emission color-tunability was realized via quantum size effect without anion–halide mixing, by varying the oleylamine to oleic acid volume ratio as surfactants, while the total amount of oleic acid remained unchanged. We are able to adjust the optical proprieties of FAPbBr3 NPLs and, consequently, their structural properties. The obtained colloidal solutions of FAPbBr3 nanoplatelets with uniform size exhibited different photoluminescence wavelengths covering the spectral region from 440 to 525 nm. The maximum absolute PL quantum yield (PLQY) of the green emission was measured to be as high as 80% at room temperature. The size of FAPbBr3 NPLs could be effectively tuned from 15.5 to 38.1 nm with an increase in the oleylamine and oleic acid ligands ratio.