bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on Effectivity and Efficiency of Various Drying Methods of Nyamplung Fruits (Callophyllum inophyllum)
Authors: Amelia Okta , Sailah Illah , Kartika Ika Amalia , Suparno Ono , Bindar Yazid 
Published: June 2022

Abstract
Nyamplung fruit has a very high industrial potential, especially for the bioenergy industry. The seeds contain high levels of oil that can be transformed into biodiesel. The advantage of nyamplung fruit as bioenergy raw material is that the seeds have a high yield can reach 74%. One of the difficulties of transforming the fruit into a product with high economic potential is in terms of taking out the seed from its shell, which is influenced by the moisture content of the fruit. To reduce the moisture content, nyamplung fruits require a drying process. The drying process is usually done by utilizing sunlight. This method has the disadvantage of taking a long time and is affected by the weather. Therefore, it is necessary to conduct a study to select one of several drying methods based on their efficiency and effectiveness. The study results showed that drying using the oven for 6 hours produced a moisture content of 10% wet base while drying using a 6-hour roasting method produced a moisture content of 6.5% wet base, and drying using sunlight for 168 hours produced a moisture content of 10.23% wet base. Water content between 6.5-10.23% makes separating seeds from their shells easy. Based on this study, it can be concluded that drying methods affect the moisture content of the fruit, and the method of drying using the oven turned out to be more effective.
Characterization of municipal solid waste for waste to energy feedstock in Jakarta
Authors: Wahyono S , Sahwan F L , Suryanto F 
Published: June 2022

Abstract
The characterization study of municipal solid waste for waste to energy facility is very important to Jakarta City because of its waste is still in mixed condition and may contains several materials those are not suitable for incinerator. The purpose of this study was to determine the character of the waste from several sources (shopping areas, office areas, industrial areas, city parks, and households) in the city of Jakarta and to analyse the quality of the waste to be feedstock of incinerator. The research used a random sampling method for the wastes which were transported to the Bantargebang final disposal site. Samples were taken proportionally from the garbage truck to determine the composition, proximate and ultimate analysis. The results showed that wastes were dominated by combustible material and had a good potential as an incinerator fuel in terms of the characteristics of moisture content (less than 50%), volatile matter (above 25%) and ash content (less than 60%), as well as its LHV (above 6 MJ/kg). However, the existence of bulky waste, hazardous waste, non-combustible waste, and several types of waste that are not allowed to enter the incinerator needs to be a concern. Those wastes potentially interfere the performance of the incinerator.
The biochar-improved growth-characteristics of corn (Zea mays L.) in a 22-years old heavy-metal contaminated tropical soil
Authors: Salam A K , Rizki D O , Santa I T D , Supriatin S , Septiana L M , Sarno S , Niswati A 
Published: June 2022

Abstract
Biochar was suggested to lower the concentrations of heavy metals in contaminated soils and therefore may improve plant growth. This research was to evaluate the growth of corn (Zea mays L.) in a biochar-amended heavy-metal-contaminated tropical soil. Soil samples were collected from well-maintained experimental plots 22 years after amendment with heavy-metal containing industrial waste at 0 – 60 Mg ha-1. Corn plants were grown for 4 weeks in the soil samples amended with biochar at 0 – 10 Mg ha-1. The corn plant height and dry masses (roots, shoots, and the whole plants) were lowered by waste in relation to the increase in the soil Cu and Zn concentrations. The corn plant dry–weight masses (roots, shoots, whole plant) were well and negatively correlated with the soil Cu and Zn concentrations. The corn plant uptake of Cu and Zn decreased with the increase in the soil Cu and Zn concentration. Biochar improved the corn plant height and dry-weight masses, related to the decrease in the soil Cu and Zn concentrations. Biochar also increased the Zn uptake at waste level of ≥ 15 Mg ha-1 and increased the Cu uptake at waste level ≤ 15 Mg ha-1. The corn plant Cu uptake was linearly and positively correlated with plant dry-weight masses of roots, shoot, and whole plant masses.
Converting of kesambi (Schleichera oleosa l.) oil into biodiesel using ZnO-based solid acid catalyst
Authors: Asri N P , Saraswati R , Yogaswara R R , Restyani N E , Suprapto S 
Published: June 2022

Abstract
Alumina-supported zinc oxide-copper oxide (ZnO-CuO/γ-Al2O3) solid catalyst which coded ZCA and zinc oxide with multi-walled carbon nanotube support (ZnO/MWCNTs) coded by ZCNT catalyst have been successfully synthesized and used to produce biodiesel from Kesambi (Schleichera olesosa l.) oil. The catalyst was synthesized using a combination of precipitation and impregnation method based on a modified Stober gel-based process. Before being used for transesterification of kesambi oil, ZCA and ZCNT catalyst was characterized using N2 adsorption-desorption followed by Brunauer-Emmett Teller (BET) calculation and Scanning Electron Microscopy (SEM) analysis. The transesterification process was conducted in a glass batch-type reactor with refluxed methanol. The effect of loading ZnO (wt.% to catalyst support) on the yield of biodiesel was investigated. The results showed that the catalyst of ZCA was potentially used for the transesterification of kesambi oil. The highest biodiesel yield above 80% was achieved after 3 hours of transesterification.
Technology innovation and business model of palm oil miniplant for food and energy
Authors: Setyaningsih Dwi , Fahma Farah , Purwoko  , Wahyudi Aria Tri , Mahendra Ilham Bintang 
Published: June 2022

Abstract
Palm oil is Indonesia’s main export commodity and has many contributions to the economy. Palm Oil Mill is built by private or state-owned company with the minimum capacity of 30 tph and far from smallholder plantations. Transportation costs and delays have caused the quality of fresh fruit bunch decrease and prices have dropped in the farmer level. This study aimed to design a palm oil mini plant by evaluating existing technology, innovating process, and equipment design, also analyzing financial aspect. The methods used in this research were literature study, laboratory test, interview, and observation. The selected process technology was sterilization using steam (t = 90 minutes, T = 130°C, P = 300 kPa), threshing with rotating speed of 21 rpm, heating method in the digester (t = 14 minutes, T = 90°C, v = 23 rpm), extraction of oil palm fruit with a screw press machine (P = 4500 kPa, v = 11 rpm). The process of refining Crude Palm Oil (CPO) gone through 3 stages, namely degumming with water degumming, neutralization using deacidification, and fractionation using the dry method to produce Refined Palm Oil (RPO). Technological innovations were carried out in vertical sterilizers with the addition of water to the sterilizer when loading the fruits, the use of augers and improvements to the sterilization system. The value propositions of palm oil miniplant business model are the ease of bureaucracy, flexibility of small-scale industry, high quality (FFA<5%), and competitive prices. The supply chain flow starts from independent smallholder plantations to oil palm miniplants without going through collectors. The products are CPO, RPO which high antioxidants activity because of tocopherols and carotenoids content, and Palm Kernel (PK). The financial feasibility analysis of palm oil mini plant resulted in an NPV of IDR 15,068,339,048, IRR of 28%, BCR of 11,7 and PBP of 2,8 years. This study showed that the palm oil mill mini plant is financially feasible to build.
Research on intelligent discrimination of cyanobacteria based on deep learning
Authors: Xu Ruicheng , Song Hongyu , Liang Hong , Kang Xiaolin 
Published: June 2022

Abstract
Dianchi Lake is the cradle of Kunming’s survival and development. It plays a vital role in the development of Kunming’s economy and society as well as the formation of a pleasant climate. The phenomenon of cyanobacteria blooms in Dianchi Lake has always been an ecological problem that has attracted much attention. Cyanobacteria blooms destroy the ecological environment, cause a large number of deaths of fish and other animals, pollute drinking water, and cause huge economic losses. In order to monitor the cyanobacteria blooms in Dianchi Lake more effectively and intelligently, this paper proposes a computer vision system for cyanobacteria discrimination based on deep learning. The neural network was trained by using the collected image data of cyanobacteria in Lake Dianchi, and then the network model was tested by using the images captured by the surveillance cameras around the lake. The experimental results show that the system can better discriminate and classify cyanobacteria blooms in different environments, and has a high recognition accuracy.
Sources and applications of biostimulants
Authors: Tang Xiting , Tian Qing 
Published: June 2022

Abstract
Efficient increase the crop yields is critical to sustain the current growing population and achieve the global food security. Bio-stimulants can stimulate crop growth and reduce the adverse effects of antibiotic stress to the plants. They are environmentally friendly and innovative substances that can be used to solve the food problems caused by the growing global population. In the context of a circular economy, the effect of recycling usful elements from waste streams to achieve resource utilization is a common concern of researchers. The components of sewage are complex, including protein, humic acid and other substances, which are potential pre-products of bio-stimulants. The recovery of biostimulants from sewage as by-products holds great promise. At this stage, however, very few literature reviews have focused on the recovery of biostimulants from wastewater. This study summaries the types, activities and recovery potentials of biostimulants from wastewater.
A Treatment Design and Operation Effect of Medical Rehabilitation Hospital Wastewater
Authors: Hong Wei , Zhang Wang , Sun Long , Li Binbin , Tan Xin , Cui Shujie 
Published: June 2022

Abstract
The process of “Classified pre-treatment + Regulating + AO treatment + Disinfection” was designed to treat the medical rehabilitation hospital wastewater, and the treatment scale was 800 m3/d. The engineering design process, main design parameters and engineering treatment effects are discussed. The stable operation results showed that when the influent concentrations of CODCr, NH3-N, SS and the enumeration of faecal coliforms were 185∼346 mg/L, 28∼55 mg/L, 55∼93 mg/L, 1.2×106∼1.4×108 MPN/L, the effluent concentrations were 22∼45 mg/L, 0.5∼3.4 mg/L, 22∼46 mg/L, 85∼220 MPN/L, which could meet the requirements of “Discharge Standard of Water Pollutants for Medical Organization in Shandong Province (DB37/596-2020)”. The direct operation cost of the project was 2.16 yuan/m3.
The impact of air pollutant emissions during the COVID-19 pandemic on Air quality in China
Authors: Chen Xuanhong 
Published: June 2022

Abstract
The outbreak of COVID-19 has led to the adoption of a series of strict epidemic prevention and control measures across the country, which has had a significant impact on people’s production and life patterns. It also provides an opportunity to explore the relationship between air quality and human social and economic activities. Based on the National Urban Air Quality Report from February 2019 to February 2021 and passenger transport capacity data from February 2019 to February 2021, the regression analysis was conducted to understand how human factors related to pollution sources affect ambient air quality levels. The study showed that passenger volume and air pollution levels decreased significantly during the epidemic period. Human factors had no significant impact on O3 concentration. However, they had a significant impact on PM, SO2, NO2, and CO. Finally, explore how to improve air quality from the Angle of human factors and build a low-carbon economy.
Study on the characteristics of vortex motion and pressure pulsation in vaneless zone of Kaplan turbine
Authors: Xue J Y , Meng C Z , Fan X F , Wang Z W , Zhou L J 
Published: June 2022

Abstract
Kaplan turbine with adjustable blade has wide operating efficiency and is widely used in medium and low head hydropower stations. Pressure pulsation has always been a key problem affecting the operating efficiency and stability of hydraulic turbines. The numerical simulation of the hydraulic characteristics of Kaplan turbine is carried out to analyze the pressure pulsation and flow distribution characteristic in the vaneless zone under different guide vane openings and blade installation angles. Results show that: At the small flow condition, vortices appear in the vaneless zone, which leads to the increase of pressure pulsation in the vaneless zone and the expansion of the fluctuation range of water moment on blade. At the small flow condition with different unit speed, the dominant frequency are observed to be between 4-5 times rotation frequency in the vaneless zone far from the runner inlet. The frequency source is that the rotating vortex flow and the rotating runner blade will form the effect similar to rotor-stator interference.The pressure pulsation observed at the monitoring point near the runner inlet mainly comes from the disturbance of the runner blade to the flow and the pressure pulsation frequency is 6fn
.
Experimental and numerical modal analysis of a reduced scale Kaplan turbine model
Authors: Roig R , De La Torre O , Jou E , Mulu B , Escaler X 
Published: June 2022

Abstract
This paper presents an experimental modal test of a Kaplan turbine model and provides the corresponding analysis of the results. The modal test of the rotor including the runner, the shaft and the generator was performed using, as exciters, an impact hammer and a shaker and, as sensors, several accelerometers. Additionally, numerical models of the rotor with the runner surrounded by air (dry condition) or submerged in water (wet condition) were also built. By comparing the numerical and experimental results, the main modes of vibration of a runner blade in dry conditions and of the rotor shaft both in dry and wet conditions have been identified and discussed. The most significant deviations between experimental and numerical natural frequencies were found around 10% for the rotor shaft and around 6% for the runner blade. Moreover, it was observed that the fourth mode of vibration presents the highest added mass effect with a Frequency Reduction Ratio of about 6.7% and the second mode of vibration shows the lowest damping ratios in both dry and wet conditions with values of about 1.5 and 2.1%, respectively.
Determination of Casting Parameters for Affirmative Directional Solidification in 750 KW Francis Runner
Authors: Kafle Abishek , Sapkota Nishan , Silwal Raman , Shrestha Pratisthit Lal , Sharma Nischal , Thapa Bhola 
Published: June 2022

Abstract
Entangled by a web-like pattern of rivers and rivulets, Nepal’s energy sector currently is dominated by hydroelectricity which sustains a major portion of the country’s economy. But still, after more than a hundred years of its operation, the sector’s dependence on imports is uncanny. This not only upsizes the project cost but also the time and human resources. The research, therefore, aims to aid the cause by examining the prospect of manufacturing runners using local industrial expertise in synchronization with available data and research. Here, the paper focuses on the sand casting of a 750KW Francis runner and the design of its parameters namely gating and feeding system to ensure directional solidification. Apart from the conventional procedure, the casting of the runner was proceeded as three separate parts: hub, shroud, and blade which were later welded together. The gate and riser placement for each of the parts was designed independently and analysed for any shrinkage porosities and possible voids using computer simulation with several iterations each. Specifically, temperature variations during three major stages of solidification assigned as 0, 50, and 100 were tested for a total of 195 nodes. The design was then transferred into the mould and casting was performed. The procedure resulted in a cast with a clean surface finish and minimal visible defects. The study, thus, suggests the possibility of manufacturing runners through metal casting and its substantial implications in the improvement of the hydropower industry in Nepal.
Rapid Analysis of Cylindrical Bypass Flow Field Based on Deep Learning Model
Authors: Jian L , Huang Z , Zhang J , Hu Z 
Published: June 2022

Abstract
Deep learning models provide a novel research perspective for hydraulic machinery and fluid dynamics mechanism research. Traditional computational fluid dynamics requires a lot of computational resource and calculation time, while deep learning models can effectively solve this problem. In this paper, a deep learning model is proposed for the rapid flow field analysis of a two-dimensional cylindrical bypass flow, and the errors of the prediction results are analyzed, so as to verify the feasibility of deep learning for accelerating the numerical simulation process. On this basis, the influence of different network structures on the prediction performance of the deep learning model is explored, and the optimal structural parameters of the neural network are found, indicating that it will achieve real-time prediction of the flow field performance, and save considerable computational resource and calculation time. The research in this paper is of great significance for the application about the rapid analysis of hydraulic machinery fluid dynamics based on deep learning models.
Development of simplified model for prediction of sediment induced erosion in Francis turbine’s sidewall gaps
Authors: Acharya Nirmal , Gautam Saroj , Chitrakar Sailesh , Dahlhaug Ole Gunnar 
Published: June 2022

Abstract
Sediment induced erosion in exposed components of hydraulic turbines is a major issue in most of the sediment laden hydropower projects. Gradual removal of material can change the components profile which can lead to change in flow characteristics and compromise in the efficiency as well. Among several components in Francis turbine, this study focuses on the runner sidewall gaps to develop a numerical model for erosion prediction. A prototype high head Francis runner with specific speed of 85.4 rpm has been considered as the reference case. A simplified numerical model based on the concept of rotating disc apparatus (RDA) is conceptualized to make analogy with the gap available between runner blades and guide vanes (GVs). Fillet gaps are introduced in the model to emulate the gaps available between runner blade and GV for real case scenario. Four samples with 90° separation of each are mounted on the disc rotating at 750 rpm. Sediment size of 150 μm diameter with particle mass flow rate based on the maximum amount of sediment passing through the reference turbine is used. Numerical calculation is done in ANSYS® with Tabakoff erosion model. Results give an indication of critical zones in the gap region. Erosion pattern, rate density and vorticity are compared with the actual turbine.
Critical speed analysis of the shafting rotor of the vertical long shaft fire pump under the different positions of the impellers
Authors: Fu L H , Yang Z J , Jin S B , Zhang J F , Song H Q , Yu X H , Zhang W J , Li G D 
Published: June 2022

Abstract
For multi-stage pumps, the change of the impeller stage spacing will have a greater impact on the dynamic characteristics of the shafting rotor. The paper took XBC18-178-240LC3 vertical long shaft fire pump as the research object, using ANSYS Workbench software to study the relationship between the critical speed of the shafting rotor and the different positions of the impellers. First, 9 shafting rotors (based Z4,Z5 and Z6 models) under the different positions of the impellers were established; and then the change law of the critical speed on 9 shafting rotors in the first 12 modes was studied. The results showed that different positions of the impeller on the shaft have a great impact on critical speed of the shafting rotor. With the increase of the distance between the impeller stages, the low-order critical speed (6th order and within) of the Z4 model shafting rotor decreases. However, the low-order critical speed (5th order and within) of the Z5 and Z6 model shafting rotors decreases with the increase of the distance between the impeller stages, and the high-order critical speed doesn’t satisfy this law. Considering static characteristics of the shafting rotor and actual engineering applications, the paper selected the Z5-stage spacing 800mm shafting rotor model as the best case, providing a theoretical support for the subsequent vertical long shaft fire pump design optimization.
Influence of Rotor Geometry on Cavitation Characteristics of Rotational Hydrodynamic Cavitation Generator
Authors: Wang X , Xie C , Zhang W , Meng G Q Q G 
Published: June 2022

Abstract
The RNG k-ε turbulence model and mass transport cavitation model are applied to simulate the cavitating flows in a rotational hydrodynamic cavitation generator with a rotor and a stator. The cavitation generator is designed to have surface dimples on the rotor. The cavitating flows analyses in cavitation generator are focused mainly in the rotor. The accuracy and reliability of the calculation model and method are demonstrated by the good agreement between with experimental and numerical results. The pressure distribution, streamline distribution and vapor volume fraction distribution in cavitation generator with five different structures (5 different diameter of rotor dimples d=11mm, 13mm, 15mm, 17mm, 19mm) under the same operation condition are analysed. The calculation results show that the characteristics of streamline and cavitaion area and pressure area are quite different based on the magnitude of the dimple diameter of the rotor. It is observed that with the rotor dimple diameter increase, the cavity bubbles firstly appear in the low pressures area of dimple bottom and develops rapidly towards the wall and top of dimple; the mass transfer between water and vapor is even more intense; the low pressures area increases in dimple and the vortex area expands and the number of vortices increases, which induces the strong turbulence on the surface of the rotor and inside the rotor. The increasing the diameter of the rotor dimple is an effective means to enhance the cavitation effect of the rotational hydrodynamic cavitation generator.