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Indonesia has targeted to reach 23% of renewable energy share by 2025. In order to meet the target, many researchers have focused on the explorations of renewable energy resources. One of the potential solutions to meet the target is the agricultural wastes, include corn cobs and areca nut fiber. In this study, the calorific value of corn cobs and areca nut fiber are tested. The corn cobs and areca nut fiber are collected from the farmers in Sumatera Utara province of Indonesia. In addition, the Paper waste is also tested. A bomb calorimeter of IKA C6000 is used to measure the energy content of the biomass. The results show that the calorific value of Corn cobs and Areca nut fiber is 5573 Cal/g and 4946 Cal/g, respectively.By using the average yearly production of Corn and Areca nut, these calorific values similar to 4,539 TOE and 4,653 TOE, respectively. If the potency can be used to replace the coal as an alternative fuel, this potency will reduce the Greenhouse gas (GHG) emission. The potency of mitigation GHG by replacing Corncob and Areca nut fiber are 18,306 and 18,491 ton of CO2e.

Leachate wastewater from pulp and paper industry is known for containing various types of heavy metals such as Cd (Cadmium), Ba (Barium) and Cu (Cuprum). The existence of heavy metals that accumulates and eventually exceeds certain threshold concentrations will cause environmental pollution, therefore it is necessary to conduct wastewater treatment to eliminate or at least reduce the heavy metal content in industrial wastewater. One of the most commonly used wastewater treatment method is using adsorbent, this study uses adsorbent made from the mixture of clay, zeolite and activated carbon formed into ceramic balls with ± 0.5 cm diameter. The ratios of the mixture of clay, zeolite and activated carbon are 6:3:1; 6:2,5:1,5; 6:2:2; 6:1,5:2,5 and 6:1:3 with variations of contact time 30, 60, 90, 120 and 150 minutes. The most favorable concentration reduction of heavy metals occurred at the longest contact time of 150 minutes at 6:3:1 adsorbent ratio, Cd concentration decreases from 0.65 mg/L to 0.03 mg /L, Ba concentration decreases from 0.86 mg/L to 0.04 mg/L and Cu concentration is from 0.6 mg/L to 0.02 mg/L. These prove that the ceramic zeolite/carbon-ceramic composite adsorbent can be an alternative to treat wastewater containing heavy metals derived from the pulp and paper industry.

The paper is focused on investigation of the nature and size of cellulose fibers in the structure of stabilizing additives for stone-mastic asphalt concrete, as well as on determination of fibers retention capacity based on their geometric parameters. To obtain the results a scanning electron microscope JSM-6510LV was used, with the help of which 15 to 20 photomicrographs were obtained. It was found out that in all inspected samples of stabilizing additives over 80% of pulp and paper fibers have a band structure with filaments from 0.56 to 1.4 micrometer in length. The fiber thickness in all cases slightly varies within the range of 0.008 to 0.021 micrometer. For a more detailed analysis of the additives the X-ray microanalysis was carried out. The results showed that in all cases the component distribution of the chemical elements present in the additive is inhomogeneous and has two fundamental differences in the oxygen (O) and carbon (C) content. ARMIDON additives contain more than 79% carbon (C) and just 6-13% oxygen (O). VIATOP 66 and SD-1 additives contain up to 61% carbon (C) and up to 48% oxygen (O). Tests to determine the runoff of the organic binder showed that additives with cellulose fiber filaments up to 0.6 micrometers in length hold bitumen worse than additives with cellulose fiber filaments 1.4 micrometers in length.The paper is focused on investigation of the nature and size of cellulose fibers in the structure of stabilizing additives for stone-mastic asphalt concrete, as well as on determination of fibers retention capacity based on their geometric parameters. To obtain the results a scanning electron microscope JSM-6510LV was used, with the help of which 15 to 20 photomicrographs were obtained. It was found out that in all inspected samples of stabilizing additives over 80% of pulp and paper fibers have a band structure with filaments from 0.56 to 1.4 micrometer in length. The fiber thickness in all cases slightly varies within the range of 0.008 to 0.021 micrometer. For a more detailed analysis of the additives the X-ray microanalysis was carried out. The results showed that in all cases the component distribution of the chemical elements present in the additive is inhomogeneous and has two fundamental differences in the oxygen (O) and carbon (C) content. ARMIDON additives contain more than 79% carbon (C) and ju...

Here, a small analytical device was fabricated on both nitrocellulose membrane and filter paper, for the detection of biotinylated double-stranded DNA (dsDNA) from 1 nM. Zif268 was utilized for capturing the target DNA, which was a zinc finger protein that recognized only a dsDNA with specific sequence. Therefore, this detection platform could be utilized for PCR result detection, with the well-designed primers (interpolate both biotin and Zif268 binding sequence). The result of the assay could be recorded by a camera-phone, and analyzed with software. The whole assay finished within 1 hour. Due to the easy fabrication, operation and disposal of this device, this method can be employed in point-of-care detection or on-site monitoring.

Synthesis of C-Dots from waste paper has been successfully created. A total of 5 grams of waste paper is mixed with 40 mL aquades, 30 mL H2SO4 and 50 mL NaOH 2 M. A precursor solution is prepared by adding urea in 20 ml of material. Synthesis of C-Dots done by heating the precursor hydrothermally using a furnace with three conditions, namely with 1-4 grams of urea, 20-50 minutes of synthesis time, and 150-300°C of temperature. In a variation of urea and time, the temperature is controlled at 300°C. In a variation of the time and temperature, urea is controlled at 3 grams. In a variation of the urea and temperature, time is controlled for 30 minutes. The maximum absorption C-Dots generated on the various of amount urea, temperature, and synthesis time in the range of 360-600 nm. The width of the absorbance area was increased by adding 1-3 grams of urea and were decreased when urea is added 4 grams or more. The absorbance peaks of C-dots decreases with increasing temperature synthesis. Meanwhile, an increasing of synthesis time does not affect to the width of the absorbance spectra. It precisely causes decreasing of peaks of the absorbance spectra. The functional groups present on the surfaces of C-dots can be identified by the presence of specific peaks in their FTIR spectra, i.e. N–H, C=C, C–N, and C–C at various urea, N–H, C=O, C=C and C–O at temperature and synthesis time.Synthesis of C-Dots from waste paper has been successfully created. A total of 5 grams of waste paper is mixed with 40 mL aquades, 30 mL H2SO4 and 50 mL NaOH 2 M. A precursor solution is prepared by adding urea in 20 ml of material. Synthesis of C-Dots done by heating the precursor hydrothermally using a furnace with three conditions, namely with 1-4 grams of urea, 20-50 minutes of synthesis time, and 150-300°C of temperature. In a variation of urea and time, the temperature is controlled at 300°C. In a variation of the time and temperature, urea is controlled at 3 grams. In a variation of the urea and temperature, time is controlled for 30 minutes. The maximum absorption C-Dots generated on the various of amount urea, temperature, and synthesis time in the range of 360-600 nm. The width of the absorbance area was increased by adding 1-3 grams of urea and were decreased when urea is added 4 grams or more. The absorbance peaks of C-dots decreases with increasing temperature synthesis. Meanwhile, an increas...

Wood fiber derived cellulose has been mainly used as the raw material in the papermaking. However, currently the paper production capacity is greater than the availability of wood. To overcome this problem, there have been many attempts to use non-wood fibers as substitutes for papermaking such as the fibrous materials derived from agriculture wastes. In this research, the paper was made from sugarcane bagasse which was previously delignified using soda process. The research was conducted by varying NaOH concentrations of 8 –16%, delignification temperatures of 60– 100°C and times of 30 –150 min. The aim of the research was to study the effect of delignification process on physical properties of sugarcane baggase soda pulping. The results showed the increase in tensile strengths as the NaOH concentrations increased. Tensile strength was increasing up to optimum temperature and time and then decreased. The water uptake results showed the opposite tendencies with those of tensile strength. The optimum condition was achieved at the NaOH concentration of 10 %, delignification temperature of 80 °C, and time of 90 min. Tensile strength and water uptake achieved at this optimum condition were 27.42 N/mm2 and 240 g/m2, respectively.

Malaysia is facing serious challenges in dealing enormous quantities of waste paper sludge produced in the country every year. This enormous quantity causing major economic problems and environmental problems over the paper and board industry. In order to confront with the economic problems associated with waste disposal costs, which make up almost half of the cost of wastewater treatment, there is a need to provide a viable solution to the reuse of waste and by reducing the use of natural resources. Hence, a comparative analysis of the experimental results novel properties of fresh and hardened concrete with recycled concrete aggregates (RCA) with different substitution of waste paper sludge ash (WPSA) as a partial substitute for cement is presented in the paper. Recycled aggregates is made by crushing the waste concrete cube laboratory tests. Recycled aggregate is made by crushing the concrete waste at laboratory. Utilize of WPSA and RCA is estimated to produce significant gains in strength performance ...

Historians and librarians are interested in watermarks and mould surface patterns in historic papers, because they represent the “fingerprints” of antique papers. However, these features are usually covered or hidden by printing, writing or other media. Different techniques have been developed to extract the watermarks in the paper while avoiding interference from media on the paper. Beta radiography provides good results, but this method cannot be widely used because of radiation safety regulations and the long exposure times required due to weak isotope sources employed. In this work, two promising methods are compared which can be used to extract digital high-resolution images for paper watermarks and these are electron radiography and low energy X-ray radiography. For electron radiography a “sandwich” of a lead sheet, the paper object, and a film in a dark cassette, is formed and it is exposed at higher X-ray potentials (> 300 kV). The photoelectrons escaping from the lead sheet penetrate the paper and expose the film. After development, the film captures the watermark and mould surface pattern Images for the paper being investigated. These images are then digitized using an X-ray film digitizer. The film employed could potentially be replaced by a special type of imaging plate with a very thin protection layer to directly generate digital Images using computed radiography (CR). For the second method, a low energy X-ray source is used with the specimen paper placed on a digital detector array (DDA). This method directly generates a low energy digital radiography (DR) image. Both methods provide high quality images without interference from the printing media, and provide the potential to generate a “fingerprint” database for historical papers. There were nevertheless found to be differences in the images obtained using the two methods. The second method, using a low energy X-ray source, has the potential to be integrated in a portable device with a small footprint incorporating user safety requirements. Differences obtained using the two methods are shown and discussed.

The micro-fibrillated cellulose crystals from natural cotton fiber via alkaline treatment and acid hydrolysis were explored as possible reinforcement in recycled paper to improve its mechanical properties. Results confirmed the characteristic properties and crystallinity of the obtained micro-fibrillated cellulose crystals. Reinforcement of the micro-fibrillated cellulose crystals in the production of recycled paper showed an improvement in the tensile strength compared to the recycled paper samples without reinforcement or even with kapok fiber/micro-fibrillated cellulose crystals combination. Further improvement on the barrier properties of the micro-fibrillated cellulose reinforced paper via biocoating made from chitosan/starch blend resulted to a 27.69% decrease of the water absorption capacity compared to uncoated sample using the Cobb test.

During recycling of waste paper from private households different fractions containing plastics and polluted paper fibers are received. Current research at the Institute of Polymer Materials and Plastics Engineering at Clausthal University of Technology showed that the use of waste paper as filler and reinforcement in polypropylene leads to nearly the same mechanical properties as natural fibers like flax, sisal and hemp. The present investigations focus on the chemical cleaning of the paper recyclate to treat the fiber surface and to solve foreign plastics like polystyrene. For this purpose Soxhlet extraction with different solvents is used. The received extracts are examined via infrared spectroscopy, as well as the treated and the untreated fibers. Afterwards, the cleaned paper is incorporated into polypropylene. The received composites are investigated regarding their mechanical properties by tensile testing and Charpy impact testing.During recycling of waste paper from private households different fractions containing plastics and polluted paper fibers are received. Current research at the Institute of Polymer Materials and Plastics Engineering at Clausthal University of Technology showed that the use of waste paper as filler and reinforcement in polypropylene leads to nearly the same mechanical properties as natural fibers like flax, sisal and hemp. The present investigations focus on the chemical cleaning of the paper recyclate to treat the fiber surface and to solve foreign plastics like polystyrene. For this purpose Soxhlet extraction with different solvents is used. The received extracts are examined via infrared spectroscopy, as well as the treated and the untreated fibers. Afterwards, the cleaned paper is incorporated into polypropylene. The received composites are investigated regarding their mechanical properties by tensile testing and Charpy impact testing.

EMG is a medical technique that measures muscle response or electrical activity in response to a nerve’s stimulation of the muscle [10]. In this paper we have classified multiple hand gestures using small number of electrodes. This report aims to review current use of EMG based control system and explain the existing challenges. The stages involved includes data acquisition, feature extraction, classification and controller. Some of the application includes Arm rehabilitation, game controller, wheel chair controllers, etc.

In this paper we report some tests regarding the feasibility of nanodiamond to act as a cleaning/consolidation agent of papers and parchments. We carried out a series of treatments aiming to develop innovative approaches for de-acidification, cleaning and consolidation. Dispersions of nanodiamond have been used as de-acidification agents of ancient papers showing the ability to sensibly reduce the acidity of the paper without using any alkaline base. Similar dispersions have been used for cleaning processes and nanodiamond demonstrated an outstanding capability to clean ancient papers and parchments avoiding the use of any solvent and surfactant. Moreover interesting results were obtained by using nanodiamond as consolidation agent. In particular, artificial aging by UV exposition was appreciably contrasted when samples were preliminarily submitted to a treatment by nanodiamond. This outcome was demonstrated in papers and parchments by Raman spectroscopy analyses that evidenced the property of nanodiamond to be an excellent UV-scavenger.

Keraton Kasepuhan Cirebon has collection of five old manuscripts of European origin from 19th century, and the former library of Faculty of Humanities Universitas Indonesia has collection of four old manuscripts of European paper origin from 19–20th centuries. The objectives of this study were to isolate and morphologically characterize fungi from nine old manuscripts of European origin. All manuscripts showed brown and black spots, and fungal spores on the surfaces. Observation by loop was carried out in the field to determine the type of paper and to detect biodeterioration of the manuscripts. Twenty-two fungal isolates were obtained by sterile cotton swab and the culture-dependent method on Dichloran Glycerol Agar (DG18). Detection of fungal deterioration on paper was investigated by using paper strip method with old paper of European origin on Czapek’s Dox Agar (CDA) without carbon source. The paper strips were inoculated with cell suspension at a concentration of approximately 1 × 107 cell/mL. Twenty fungal isolates were able to grow on the old paper strips indicating that the old manuscripts are liable to fungal degradation. The fungal isolates were xerophilic in nature. Morphological characterization described the fungal isolates in the genera of Aspergillus, Penicillium, and Eurotium. Three fungal isolates could not be described and were grouped as Mycelia sterilia. Basic local alignment search tool (BLAST)-based identification and phylogeny-based identification using the data set of internal transcribed spacer (ITS) sequences is required to determine the species identities of the fungal strains.

Keraton Kasepuhan Cirebon and the former library of Faculty of Humanities Universitas Indonesia have collections of old manuscripts of European paper origin from 19-20th centuries. This study investigated the cellulolytic and xerophilic characters of 22 fungal strains from nine deteriorated old manuscripts of European paper origin. Detection of cellulolytic fungi by using well diffusion method, modified Czapek’s Dox Agar (CDA) with 0.1% (w/v) carboxymethyl cellulose (CMC) as a sole carbon source, 0.2% (w/v) Congo red as a chromogenic dye, and cell suspension of approximately 1x107 cell/mL. Cellulolytic fungi formed clear zones around the fungal colonies due to the radial diffusion of the enzyme excreted to the medium. Detection of xerophilic fungi by using Dichloran glycerol Agar (DG18) which contained 18% glycerol to reduce water availability in the medium. Fifteen fungal strains have the ability to use derivative cellulose in CMC as a sole carbon source indicating that these strains possessed endoglucanase (CMCase) activity. The action of cellulolytic enzyme from fungi could dissolve cellulose fibers, or might discolor the paper. All the fungal strains were xerophiles, which indicated that they were able to grow in manuscripts, a condition of reduced water activity. Further studies are required to determine exoglucanase activity by using crystalline cellulose, and molecular identification by using internal transcribed spacer (ITS) sequences to determine the species identities of the fungal strains.

The commercial telecommunication system in future would explore the electromagnetic spectrum with higher frequency than used now, because it requires higher speed of transmission data. Using the millimeter waves (mmW) with frequency ranging from 30 to 300 GHz, such requirement could be fulfilled. The upcoming 5G cellular technology is expected to use frequency 30 GHz or higher. Then materials with a specific characteristic at the mmW range are interesting to be explored and investigated. Here, we report the synthesis process of graphene/TiO2 deposited on paper and their transmission characteristics to the electromagnetic energy at frequency 27-40 GHz (Ka-Band). The reduced graphene oxide (rGO) was synthesized by a modified Hummers method with introduction of microwave irradiation in the process. rGO and TiO2 were mixed in ethanol solution and deposited on the paper by a spraying technique. Transmission coefficient of electromagnetic wave energy at Ka-Band was measured by using the millimeter vector networ...

The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that use a magnetic field. The applications for magnetic sensors that have been studied include 1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, 2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and 3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.

The infrared (IR) spectra of different white copy paper types tend to appear indifferent. Discrimination between white copy papers could lead to the solution of forgery cases. In this preliminary study, three varieties of white paper were purchased from local stationery shops in Kuala Lumpur, Malaysia. The papers were classified according to their manufacturers using Partial Least Squares-Discriminant Analysis (PLS-DA) and sparse PLS-DA (sPLS-DA) models. The error rate for the two models on the training and the test data sets were estimated and compared. Results show that the performance of the two models are comparable. By including the first six latent variables in both models, classification accuracy as high as 100% can be achieved.

This paper presents the laboratory result on compaction characteristic for soft soil subgrade which was stabilized by using waste paper sludge ash (WPSA). The soft soil sample was collected from Banting Selangor, Malaysia named as Banting soft soil and classified as slightly sandy Clay with intermediate plasticity. Additive of WPSA is a finely waste product produced from the incinerated waste paper. In ASTM C618, this WPSA samples are categorized as Type-C fly ash due to the high free lime (CaO) content (>20%) and possesses some cementitious and pozzolanic, resulting in the self-cementing characteristics. Therefore no entire activators such as lime are required. Objectives of this study are to determine the dry density and moisture content of Banting soft soil stabilized by WPSA through the different energy and method of compaction and to determine the Atterberg limit properties of Banting soft soil stabilized using WPSA. Several percentage of WPSA (4%, 8%, 12% and 16%) was used to stabilize the soft soil...

The use of digital tools in algebra education is expected to not only contribute to master skill, but also to acquire conceptual understanding. The question is how digital tools affect students” thinking and understanding. This paper presents an analysis of data of one group of three grade seventh students (12-13 year-old) on the use of a digital tool for algebra, the Cover-up applet for solving equations in particular. This case study was part of a larger teaching experiment on initial algebra enriched with digital technology which aimed to improve students” conceptual understanding and skills in solving equations in one variable. The qualitative analysis of a video observation, digital and written work showed that the use of the applet affects student thinking in terms of strategies used by students while dealing with the equations. We conclude that the effects of the use of the digital tool can be traced from student problem solving strategies on paper-and-pencil environment which are similar to strategies while working with the digital tool. In future research, we recommend to use specific theoretical lenses, such as the theory of instrumental genesis and the onto-semiotic approach, to reveal more explicit relationships between students” conceptual understanding and the use of a digital tool.

Selection of the most significant variables, i.e. the wavenumber, from an infrared (IR) spectrum is always difficult to be achieved. In this preliminary paper, the feasibility of genetic algorithms (GA) in identifying most informative wavenumbers from 150 IR spectra of papers was investigated. The list of selected wavenumbers was then employed in Linear Discriminant Analysis (LDA). GA procedure was repeated 30 times to get different lists of variables. Then the performances of LDA models were estimated via leave-one-out cross-validation. A total of six to eight wavenumbers were identified to be valuable variables in the GA procedures. All the 30 LDA models achieve correct classification rates between 97.3% to 100.0%. Therefore the GA-LDA model could be a suitable tool for differentiating white papers that appeared to be highly similar in their IR fingerprints.

We successfully developed a method utilizing colloidal CdSe nanocrystalline quantum dot for anti-counterfeiting label on a piece of glossy paper. We deposited numbers and lines patterns of toluene soluble CdSe quantum dot using rubber stamper on a glossy paper. The width of line pattern was about 1-2 mm with 1-2 mm separation between lines. It required less than one minute for deposited CdSe quantum dot on glossy paper to dry and become invisible by naked eyes. However, patterned quantum dot become visible using long-pass filter glasses upon excitation of UV lamp or blue laser. We characterized photoluminescence of line patterns of quantum dot, and we found that emission boundaries of line patterns were clearly observed. The error of line size and shape were mainly due to defect of the original stamper. The emission peak wavelength of CdSe quantum dot was 629 nm. The emission spectrum of deposited quantum dot has full width at half maximum (FWHM) of 30-40 nm. The spectra similarity between deposited quant...

On-line measurement of material properties is a goal of many manufactures for production improvement and quality control. In the paper industry, the elastic stiffness of the paper web needs to be accurately measured and controlled online. Currently, contact ultrasonic methods are employed to measure the elastic constants of paper offline. Piezoelectric transducers are placed in contact with the paper surface to generate and detect plate wave modes, known as Lamb wave modes, in the paper in both the machine and cross directions. Laser ultrasonics offers a new approach to making elastic wave measurements that does not require contacting the paper web. A pulsed laser generates ultrasound in the paper by delivering a high intensity short impulse to the paper through thermoelastic expansion. An optical interferometer is used to demodulate the small phase modulation that the elastic wave produces on a continuous probe laser beam. Difficulty in applying this approach to online measurements of rapidly moving pape...

Pineapple has been known for a number of beneficial biological activities such as anti-oxidative and anti-browning. Some of these bioactivities are contributed by enzymatic complex in pineapple and it can be found mainly in the skin extracted pineapple juice. The purpose of this study is to determine the effect of the pineapple juice as a pulping and bleaching agent in the process of papermaking. During pulping of pineapple leaf fibre, the mixture of pineapple juice/water was added together with a constant amount of 3% Sodium Hydroxide (NaOH) at various concentration of pineapple juice (0%, 20%, 40%, 60% and 80%). Pineapple leaf fibre (PALF) was soaked several times with pineapple juice and NaOH during pulping and bleaching process in order to get the optimum results of the paper sheet obtained. The mechanical and physical properties of paper sheet were studied by measuring its tensile strength, tear resistance and water absorption. Comparatively, paper sheet produced from NaOH pulping shows better mechanical and physical properties than the mixture pulping of NaOH and pineapple juice. Additionally, pulping with higher concentration of pineapple juice tends to give long fibre rather than short fibre. Overall, the results of this study can be used as an alternative way in the production of paper and it also opens a door to utilize wisely the waste residue of pineapple in other sectors.

The needs for clean and safe water are growing as the population growing as well. This paper describes the variation of Wastewater Percentage and Pinch Point Temperature Difference (PPTD) on a 50 MW Steam Power Plant. After using the cooling water, not all water is discharged back to the sea, some of the water are used in throttling process where some of water will be vapor, and the other are merged with the water from water treatment and are going to be used for cooling cycle. It’s found that by decreasing the condenser pressure from 8.45 kPa to 6.45 kPa it will produce vapor that could be condense into Aquadest with SEC (Specific Energy Consumption) at best condition as much as 697.85 kJ for producing 1 kg of Aquadest on PPTD 4.3 °C. On that condition, Aquadest could be produced at 0.0178 kg/s rate and the efficiency of turbine increase about 0.16%. Another benefit of this system is that this system discharges cooler water from the process, and has less impact to the environment.The needs for clean and safe water are growing as the population growing as well. This paper describes the variation of Wastewater Percentage and Pinch Point Temperature Difference (PPTD) on a 50 MW Steam Power Plant. After using the cooling water, not all water is discharged back to the sea, some of the water are used in throttling process where some of water will be vapor, and the other are merged with the water from water treatment and are going to be used for cooling cycle. It’s found that by decreasing the condenser pressure from 8.45 kPa to 6.45 kPa it will produce vapor that could be condense into Aquadest with SEC (Specific Energy Consumption) at best condition as much as 697.85 kJ for producing 1 kg of Aquadest on PPTD 4.3 °C. On that condition, Aquadest could be produced at 0.0178 kg/s rate and the efficiency of turbine increase about 0.16%. Another benefit of this system is that this system discharges cooler water from the process, and has less impact to the environment.

Human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) is pandemic. It has affected nearly 60 million people since the detection of the disease in 1981 to date. In this paper basic deterministic HIV/AIDS model with mass action incidence function are developed. Stability analysis is carried out. And the disease free equilibrium of the basic model was found to be locally asymptotically stable whenever the threshold parameter (RO) value is less than one, and unstable otherwise. The model is extended by introducing two optimal control strategies namely, CD4 counts and treatment for the infective using optimal control theory. Numerical simulation was carried out in order to illustrate the analytic results.

Bio-energy is renewable energy made from plant. Biomass-based energy sources are potentially CO2 neutral and recycle the same carbon atoms. In order to reduce pollution caused by fossil fuel combustion either for mechanical or electrical energy generation, the performance characteristic of purified palm oil blends are analyzed at various ratios. Bio-energy, Pure Plant Oil, represent a sustainable solution.A generator has been modified due to adapt the viscosity ofblended fuel, PPO - diesel, by pre-heating. Several PPO - diesel composition and injection timing were tested in order to investigate the characteristic of mixed fuel with and without pre-heating. The term biofuel refers to liquid or gaseous fuels for the internal combustion engines that are predominantly produced fro m biomass. Surprising result showed that BSFC of blended PPO - diesel was more efficient when injection timing set more than 15° BTDC. The mixed fuel produced power with less mixed fuel even though the calorie content of diesel is higher than PPO. The most efficient was 20% PPO in diesel with BSFC 296 gr fuel / kwh rather than 100% diesel with BSFC 309 gr fuel / kwh at the same injection timing 18° BTDC with pre-heating. The improvement of BSFC is caused by heating up of mixed fuel which it added calorie in the mixed fuel. Therefore, the heating up of blended PPO - diesel is not only to adapt the viscosity but also improving the efficiency of fuel usage representing by lower BSFC. In addition, torque of the 20% PPO was also as smooth as 100% diesel representing by almost the same torqueat injection timing 15° BTDC. The AIP Proceedings article template has many predefined paragraph styles for you to use/apply as you write your paper. To format your abstract, use the Microsoft Word template style: Abstract. Each paper must include an abstract. Begin the abstract with the word “Abstract” followed by a period in bold font, and then continue with a normal 9 point font.

We extracted natural Eucommia ulmoides gum and studied its application in natural rubber tire compounds in this paper. The result showed that addition of Eucommia ulmoides gum could improve the properties of Natural rubber tire compounds greatly.We extracted natural Eucommia ulmoides gum and studied its application in natural rubber tire compounds in this paper. The result showed that addition of Eucommia ulmoides gum could improve the properties of Natural rubber tire compounds greatly.

Demand for fossil fuel of coal, petroleum and natural gas has always increased from year to year. Therefore, the development, expansion and utilization of biomass from non no-fossil fuels need be carried out. Efforts to explore, develop, process and utilize biomass from non-fossil fuels, which is the cultivation of microalgae containing triglycerides that can be extracted into methyl esters (biodiesel). The sample extraction process is carried out in 5 stages, such as harvesting, weaving, methylation, extraction, and washing. The amount and ratio of saturated and unsaturated fatty acid is a key that determines the suitability of microalgae as a biofuel feedstock. This paper aims to compare the potential microalgae in Indonesia with the other countries as feedstock for biofuel production. The fatty acid composition of Synechococcus sp. HS-9, Spirulina platensis, Glagah consortium microalgae, and Nostoc HS-20 from Indonesia could be a promising feedstock for biofuel production. The quantity of fatty acid microalgae from Indonesia higher than the other countries.

The concept of using network centrality measures in the selection process of memetic differential evolution algorithm is proposed. The usual aim for introducing changes in global optimization algorithms is to make it perform better. This short paper does not intend to provide enough experimental details to decide upon the performance of the new method, nevertheless, we definitely obtain interesting insights on how the discovery of local optima were done.

The improvement of air pollution issues and excessive road transportation dependence on crude oil is not possible today without the implementation of new mobility concepts, preferably complying with the principles of sustainable social and economic development. The lack of these concepts, as emphasized in the White Paper, Roadmap to a Single European Transport Area – Towards a competitive and resource efficient transport system, will preserve transportation dependence on crude oil so deeply that only 10% of energy will be derived from renewable sources. According to this scenario, until 2050 the CO2 emissions in the transportation sector will increase by one third compared to 1990. Moreover, there will be an increase in the costs of traffic congestion until 2050 by ca. 50%. The difference in availability between central and peripheral areas and social costs of accidents and noise pollution will increase as well [1].

Recently, there has been considerable attention in the development of biodegradable plastic. Our current use and disposal of synthetic-based conventional plastics caused high rates of land-fill problems because of its persistence in the environment. Many renewable resources have been used as a source of starch and cellulose as bioplastic constituents. One of the most available biomasses that have not been explored is water hyacinth (Eichornia crassipes). In the present study, we investigated the fabrication of biodegradable plastic made with a matrix of 3% and 5% mixture of starch and cellulose extracted from water hyacinth in different weight ratios of 10:0, 9:1, 8:2, and 7:3. The addition of water hyacinth cellulose was purposed as a reinforcing agent to improve the performances of the starch bioplastics. Chitosan with a matrix of 1% was also added to improve the mechanical function of starch bioplastic. There were two main steps performed to isolate water hyacinth cellulose, i.e., bleaching and alkali treatment. The chemical and physical characteristics of starch-based bioplastics and their composites were then analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Moreover, the tensile strength and bioplastic degradation tests were also conducted to study the performance and biodegradability. The FTIR data shows that the functional group’s absorption revealed corresponds to the pure cellulose indicating the successful cellulose isolation from water hyacinth. The tensile strength of bioplastic starch- chitosan increases with the addition of water hyacinth cellulose. The improvement of the physical properties of bioplastic starch was achieved through the addition of chitosan and water hyacinth. The mixture of starch-chitosan combined with water hyacinth cellulose produces environmentally friendly bioplastics shown by the increased mechanical and physical properties compared to starch-alone bioplastic.

This research aimed to determine the effects of catfish meat addition to the fulfillment of protein and vitamin A (beta-carotene) and to study physicochemical properties (density, iron, beta-carotene, and proximate) in instant baby porridge using the drying method of the freeze dryer. Fish meat is added to fulfill the content of instant baby pulp protein in accordance with SNI. Baby porridge is dried using a freeze dryer tool which then becomes a form of instant baby pulp. The baby porridge sample was compared with baby control porridge (without fish meat addition) which was the result of previous studies. This research used a completely randomized design with one factor, namely variation in the percentage of catfish as 7.5%, 10%, and 12.5%. The results showed the addition of catfish meat with variations in the concentration of fish meat influenced the nature of the content both physically and chemically. The best baby porridge in terms of chemical properties in meeting the needs of protein and vitamin A (beta-carotene) was found in instant baby porridge with 10% concentration of catfish meat for protein and baby porridge and 7.5% concentration of catfish meat for vitamin A. The addition of catfish meat provided good chemical properties than control sample.

The research which had been conducted in March–June 2019 had the purpose of determining the effect of water spinach (Ipomoea aquatica) on BOD and COD levels in Krebet Sugar Mill wastewater with phytoremediation technique. The research used the posttest-only control group design. Liquid waste experiments were taken at three points on the waste stream using water spinach (Ipomoea aquatica) with three repetitions. Data analysis using statistical description by comparing each data obtained from the treatments with controls. The results of the study showed that the Krebet Sugar Mill wastewater treatment using water spinach plants (phytoremediation technique) was able to reduce BOD parameters by 5.49 mg/L at the first point; 2.53 mg/L at the second point; and 5.20 mg/L at the third point; while COD parameters was 7.79 mg/L at the first point; 12.56 mg/L at the second point; and 12.15 mg/L at the third point. The conclusion of this research is the phytoremediation technique using water spinach plants influential can reduce the levels of BOD and COD in liquid waste.

Water filter has been made to improve well water quality by using filtration concept in which activated carbon from cocoa rind waste and clay was used. The filter was made by varying the composition of cocoa rind waste and clay in activated carbon at the ratios of 85%:15%, 80%:20%, 75%:25%, 70%:30% and 65%:35%. The combustion temperature was varied at 200°C, 230°C, 260°C, 290°C and 320°C. Then it was molded by using mold and press conventional technique. The characterization results showed optimum composition was reached at 65%:35% ratios under 320°C combustion where the absorbance and porosity of water filter were at 86% and 52.38% respectively. Whereas density of 0.617 g/cm3 and 0.00514 MPa compressive strength were obtained from 85%:15% composition at 200°C combustion temperature. The performance test for the filter in purifying well water gave 3.2 NTU for turbidity, 7 TCU for color, 338 µS/cm conductivity, 6.7 pH level and Fe content of 1.0 mg/L. The analysis done showed that the water filtered has met the standard quality of clean water.

The use of magnetite nanoparticles to produce magnetic paper has a severe effect on the color of the paper, which is worth searching means to alleviate. Multicore-shell Fe3O4-SiO2 magnetic nanocomposites were synthesized. The nanocomposite powder was dispersed in cellulose pulp and paper was produced by dehydration on a Rapid Kothen machine. The nanocomposite retention efficiency was investigated in correlation with nanocomposite shell thickness, the resinous vs. deciduous fiber content of the cellulose pulp, the long and short fibers’ grinding degree, the cationic starch and polymeric retention agent content of the pulp. The whiteness and magnetization was measured for all paper samples. It was proved that the use of multi-core shell magnetic nanocomposites leads to weaker paper coloring. This effect is enhanced by increasing the polymeric retention agent content of the pulp, in spite of higher composite content.

Aerobic granular sludge technology can be one of the solutions to extend wastewater treatment plant when a limited space is available, besides Sequential Batch Reactor or biofilm carrier media technologies. This paper presents a comparative study between two types of technologies, Sequential Batch Reactor (SBR) and Granular Sequencing Batch Reactor (GSBR), using BioWin simulations based on the designed data of a wastewater treatment plant. Efficiencies of both technologies are studied regarding organic load and nutrients.

Oil palm fronds are one of the most promising agricultural lign ellulosic residues for bioethanol production and for adding value to chemical feedst ks in Indonesia and South Kalimantan. Currently, hydrothermal pre-treatment has attracted a great deal of attention because it only uses chemical-free water, which is a non-toxic, inexpensive, and environmentally friendly method to enhance enzymatic digestibility in the production of fermentable sugars. In this study, oil palm fronds were treated at temperatures ranging from 170 to 210°C for 30 minutes in a batch aut lave. The effect of the temperature and time of hydrothermal pre-treatment on the characteristics of the oil palm fronds and the amount of reducing sugar was expressed as a severity factor (log R0). Furthermore, after the hydrothermal pr ess the changes in the mass loss, color of substrates, and the pH of filtrate were evaluated. From these results, the mass loss and pH indicated that the optimum severity factor for hydrothermal treatment was 4.72. Additionally, the alteration to the oil palm frond structure was confirmed by Fourier Transform Infrared (FTIR) spectroscopy. Finally, 48.8% (w/v) fermentable sugars were obtained from enzymatic hydrolysis using cellulase enzyme at the newly determined maximum severity factor of 4.72.At the request of all authors of the paper an updated version of this article was published on 29 November 2018. The original version supplied to AIP Publishing contained incorrect corresponding author information; the corresponding author is only sunardi@ulm.ac.id, and many typographical errors. These errors have been corrected in the updated and re-published article.

This paper reports results of an investigation on the blended BWA-FA geopolymer mortars prepared by the inclusion of biomass wood ash (BWA) as a partial replacement material for fly ash (FA). The blended mortar systems were prepared at three replacement ratios of FA by BWA of 5%, 15% and 25% by binder mass. The engineering properties of compressive strength, water absorption and total porosity measurements obtained at different ageing of 3, 7 and 28 days, were used to assess the blended systems against a control mortar mix containing 100% FA. The results showed that the inclusion of BWA up to 15% resulted in higher strength and durability characteristics than the control mix at age of 3 and 7 days. However, at age of 28 days, the geopolymer containing 10% BWA of the total binder was the only blended mixture exhibited higher compressive strength and lower total porosity than the control mix.

A sensitive dip test strip for detection of formalin (HCHO) in tofu samples based on immobilized pararosaniline (PR) has been developed. The test strip has been fabricated by immobilizing PR reagent on filter paper. By using image color analysis (ImageJ) as the average of ΔRGB value as color sensor response, the analytical parameters are obtained from an area of the sensing zone of the test strip using digital output of the color scanner. By using this scanometric method, it is possible to determine HCHO as low as 0.05 mg/L with the concentration range of 2-80 mg/L and the response time of 3 minutes. The reproducibility was found to be 8.04% (RSD) for good recovery. The test strip has been successfully applied to detect formaldehyde in tofu samples, and the results show in good agreement with the Nash method using UV/vis spectrophotometry.

The paper focuses on the development of a low-cost biogas filtration system for alternating current generator to achieve higher efficiency in terms of power production. A raw biogas energy comprises of 57% combustible element and 43% non-combustible elements containing carbon dioxide (36%), water vapor (5%), hydrogen sulfide (0.5%), nitrogen (1%), oxygen (0 – 2%), and ammonia (0 – 1%). The filtration system composes of six stages: stage 1 is the water scrubber filter intended to remove the carbon dioxide and traces of hydrogen sulfide; stage 2 is the silica gel filter intended to reduce the water vapor; stage 3 is the iron sponge filter intended to remove the remaining hydrogen sulfide; stage 4 is the sodium hydroxide solution filter intended to remove the elemental sulfur formed during the interaction of the hydrogen sulfide and the iron sponge and for further removal of carbon dioxide; stage 5 is the silica gel filter intended to further eliminate the water vapor gained in stage 4; and, stage 6 is the activated carbon filter intended to remove the carbon dioxide. The filtration system was able to lower the non-combustible elements by 72% and thus, increasing the combustible element by 54.38%. The unfiltered biogas is capable of generating 16.3 kW while the filtered biogas is capable of generating 18.6 kW. The increased in methane concentration resulted to 14.11% increase in the power output. The outcome resulted to better engine performance in the generation of electricity.

Acacia Mangium and Eucalyptus Pellita had been used as raw material of pulp in Indonesia. In this research 5-year old of the wood were pulped under different active alkali charge varied at 16, 17, 18, 19 and 20% and its effect on pulp yield, pulp viscosity and kappa number was investigated. The cooking was done in a rotating digester Haato 6 chambers and 300 gram of dry mass chips were used, with sulfidity 25%, H-factor 800, temperature 165˚C and ratio between chips and liquid was 1: 3,5. The pulp screened yield indicates that decreased from 53,7 to 52,25% for acacia mangium and 53,0 to 50,6% for eucalyptus pellita when active alkali charge increased. Kappa number decreased from 19,0 to 16,8 for acacia mangium and 16,69 to 13,4 for eucalyptus pellita when active alkali charge increased. The viscosity decreased from 818 to 378 ml/g for acacia mangium and 697 to 426,8 ml/g for eucalyptus pellita when active alkali charge increased.

Hybrid Power Plant, which uses solar energy and in situ fuels such as pure coconut oil (PCO) and pure palm oil (PPaO), could be a solution for electricity problem in remote areas in Indonesia. Comparison of performance, and emissions are discussed and analyzed in this paper. For performance parameter, efficiency of hybrid system averages 7% higher compared with diesel engine. BSFC of diesel engine average value by using PPaO and PCO are 7.2% and 4.7% higher than by using diesel fuel. However, the BSEC average values are 4.5% and 3.3% lower than the diesel fuel. For the emission parameters, average value of CO2 emissions from the hybrid system is 21.7% lower than the diesel engine, but average value of CO emissions is 31% higher compared to diesel engine. Significant differences can be observed at average value of NOx emissions by using PCO and PPaO which are 210% and 117% lower compared to the diesel fuel.

Scarcity in fuel from fossil fuel has led to exploration of potential substitutes from renewable sources. Biodiesel as one of renewable energy sources is identified as cleaner alternative to petroleum fuel. This paper reports on the study of potassium carbonate, K2CO3 sourced from pineapple and orange peels as heterogeneous catalyst for biodiesel production. K2CO3 was produced by drying of fruit peel prior to calcination at temperature ranged from 700°C to 1000°C for 2 to 4 hours. To determine the physicochemical properties of the resulting ash, Fourier transform infrared (FTIR) and Scanning electron microscopy (SEM) analysis were employed for the characterization of the solid. Through FTIR analysis, the presence of carbonate was confirmed while SEM analysis revealed the morphological properties of the catalyst. Biodiesel with highest yield of 95.6% was produced at 60°C, 2.75 wt% of catalyst and 12:1 molar ratio of methanol to oil.

Drying is one way of post-harvest handling to extend the shelf life, especially for agricultural crops. In general, post-harvest drying is only done naturally by using heat from solar energy or commonly called conventional drying. In this study, the grain was dried using a fluidized bed dryer. However, the fluidized bed dryer was modified by adding a pipe heat exchanger. The purpose of this study was to find the effect of grain mass and air intake temperatures on drying time. The Indonesian government has carried out SNI provisions for milling the maximum water content in the material which is 14%. In this study, the grain used was the newly harvested grain where the water content was about 20% with a tolerance of ± 1%. The mass variations in this study were 0.4 kg, 0.6 kg and 0.8 kg and the temperature variations applied were 55°C, 60°C, and 65° C. The results showed the highest heat loss occurs at the highest mass because the air velocity is not able to circulate properly.Drying is one way of post-harvest handling to extend the shelf life, especially for agricultural crops. In general, post-harvest drying is only done naturally by using heat from solar energy or commonly called conventional drying. In this study, the grain was dried using a fluidized bed dryer. However, the fluidized bed dryer was modified by adding a pipe heat exchanger. The purpose of this study was to find the effect of grain mass and air intake temperatures on drying time. The Indonesian government has carried out SNI provisions for milling the maximum water content in the material which is 14%. In this study, the grain used was the newly harvested grain where the water content was about 20% with a tolerance of ± 1%. The mass variations in this study were 0.4 kg, 0.6 kg and 0.8 kg and the temperature variations applied were 55°C, 60°C, and 65° C. The results showed the highest heat loss occurs at the highest mass because the air velocity is not able to circulate properly.