Rich Products Research Articles

Biodegradation of Sugarcane Trash with Agro-Industrial and Farm Wastes for Value Added Organic Byproduct

Arable land degradation, agro-waste management coupled with irrational use of chemicals has led to concern about soil and environmental health. The sugarcane crop generates lot of vegetative biomass after harvesting, which is burnt in field creating environmental implications. A research trail was conducted at green house premises department of soil and environment SAU Tandojam. The waste byproducts of the sugarcane trash was blended with pressmud, poultry and goat manure to have decomposed nutrient rich product subjected to 130 days decomposition/composting. Results revealed that the pH had significant relationship with organic substrate decomposition used for the compost preparation blended with sugarcane trash. The organic carbon loss or mineralization showed great variability and had relationship with the substrate used and decomposition time for a finished product. The more organic carbon (31.80%) was recorded for Cspm and (31.80%) C was found for Cpm. Compost product was rich in carbon potassium values corresponding (4.6%) for Cspm and (2.7%) K for Cgm. It was concluded that sugarcane trash can best be blended with sugarcane press mud of agro-industrial waste. Further it could be recycled with agro-industrial waste for waste management, reduce pollution, chemical fertilizers and used as organic soil amendment.

Hydrothermal gasification of Scenedesmus obliquus and its derivatives: a thermodynamic study using Aspen Plus

AbstractThis study presents the simulation of hydrothermal gasification (HTG) of Scenedesmus obliquus microalgae and their derivatives using Aspen Plus V11. The effect of operating parameters such as temperature, pressure, and biomass concentration on the yield and composition of gaseous products using whole algae, lipid, and lipid extracted algae (LEA) as feedstocks was examined. The results showed that reaction pressure exhibited minimal impact whereas temperature, biomass concentration, and feedstock composition had significant effects on the composition of gaseous products. It was also found that a low temperature (400 °C) and biomass concentration of 40 wt% favored the production of methane‐rich gas. In contrast, high temperature (700 °C) and low biomass concentration (10 wt%) favored hydrogen‐rich gas production in all the three feedstocks considered. The highest mole fraction achieved for CH4 was 53.45, 61.70, and 52.20 mol%, which corresponded to a CH4 yield of 31.14, 56.90, and 30.15 mmol g−1 for whole algae, lipid, and LEA respectively. For H2 rich gas production, the highest mole fractions achieved were 55.77, 52.29, and 55.34 mol%, which correspond to H2 yields of 75.44, 105.51, and 73.49 mmol g−1 for whole algae, lipids, and LEA, respectively. The ranking order for the yield and lower heating value of the product gas from the HTG process is lipid > whole algae > LEA. This study has shown that hydrogen‐rich and methane‐rich gas can be produced from the hydrothermal gasification of microalgae as a function of the reaction conditions and feedstock composition. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Diventare umano. Dalla memoria culturale ai nuovi sensi di appartenenza: storie di migrazioni negli albi illustrati contemporanei

This contribution aims to investigate the complex, transformative role children's literature can play in today’s socio-cultural context, offering a creative platform, not only in terms of plot or contexts, but also in terms of stylistic research and the book as a medium, on which to build new ways of thinking about and designing reality. The work focuses specifically on one of the most significant picture books on the topic of (real or metaphoric) migration, refugees, migrants’ difficult and controversial path to integration. The very rich production in recent years has, with different registers each time, emblematically interpreted the political vocation of contemporary children's literature, formulating relations with otherness, encouraging the deconstruction of cultural stereotypes and preventing emotional anaesthesia in the face of issues that demand the precise assumption of human and civil responsibility. In formal terms, it investigates the narrative strategies adopted by the authors and illustrators to guide the empathic involvement of the reader, aiming to foster reflexive and pro-social attitudes. In the picture books examined, the representation of the refugee, the stateless, the “destined to death”, to quote Hanna Arendt, for whom the loss of citizenship equals the denial of the most basic human rights, challenges the “danger of a single history”.

Regenerative medicine: characterization of human bone matrix gelatin (BMG) and folded platelet-rich fibrin (F-PRF) membranes alone and in combination (sticky bone)

During the last two decades autologous platelet and leukocyte rich products (PRP; PRF), opened new perspectives in regenerative medicine. In particular regenerative dentistry played a pioneer role in the application of these products in bone regenerative cases. Many aspects of cytokines, such as, growth factor release, blood cell content and its characterization were reported, but some practical questions are still unanswered in the preparation of PRF membranes and sticky bones. A new folding technique was introduced that created a good quality, pliable, and strong F-PRF membrane with a dense fibrin network and more homogenous blood cell distribution. F-PRF produced a very promising sticky bone combined with human freeze-dried cortical bone matrix gelatin (BMG). There hasn’t been much focus on the quality and character of the applied bone and the optimal membrane/bone particle ratio has not been reported. A 0.125 g BMG/ml plasma (1 g/8 ml) seems like the ideal combination with maximal BMG adhesion capacity of the membrane. Particle distribution of BMG showed that 3/4 of the particles ranged between 300–1000 µ, the remnant 1/4 was smaller than 300 µ. The whole F-PRF membrane and its parts were compared with conventional A-PRF membrane concerning their resistance against proteolytic digestion. The F-PRF was superior to A-PRF, which dissolved within 4–5 days, while F-PRF was destroyed only after 11 days, so this provides a better chance for local bone morphogenesis. The F-PRF pieces had similar resistance to the whole intact one, so they can be ideal for surgical procedures without risk of fast disintegration.

Homeostasis Regulating Factors, Innervation, Ischemia and Inflammatory Markers in the Right Atrial Tissue from Patients with Degenerative Aortic Valve Stenosis and Coronary Heart Disease

Abstract Both coronary heart disease (CHD) and degenerative aortic valve (AoV) stenosis have common risk factors, such as age, high blood cholesterol, diabetes, smoking, high blood pressure, inflammation, and metabolic syndrome. However, these diseases are not always observed together, confirming the existence of risk and pathogenesis factors specific to each disease. The aim of this study was to identify presence and distribution of common and different homeostasis regulating factors, innervation, ischemia and inflammatory markers in the right atrial tissue from patients with degenerative AoV stenosis and CHD. During elective cardiac surgery, right atrial tissue fragments were taken from 20 patients with CHD and from 9 patients with degenerative AoV stenosis. All tissue fragments were stained for immunohistochemical detection of protein-gene peptide 9.5 (PGP 9.5), atrial natriuretic peptide (ANUP), vascular endothelial growth factor (VEGF), chromogranin A, endothelin, interleukin 1 and 10 (Il-1 and Il-10) and β defensins 2, and 3 (βD2 and βD3). For the quantification of structures, a semi-quantitative counting method was used. Mostly numerous Il-10 positive cardiomyocytes and epi-/endocardial endothelial cells were detected in all specimens taken from patients with CHD, and statistically more than in specimens taken from patients with degenerative AoV disease (p = 0.007 and p = 0.016). Also, the number of βD3 positive cardiomyocytes was higher in the coronary heart disease group (p = 0.026). All other tested markers such as PGP 9.5, ANUP, VEGF, endothelin, chromogranin A, Il-1 and βD2 showed similar expression in both groups. Increased production of ANUP in right atrial tissue characterises both CHD and degenerative AoV stenosis. Production of ChgA in right atrial endocardial endothelial cells might represent regulation of sympathetic activity as a compensatory homeostatic response. Increased PGP 9.5-containing innervation is characteristic in patients with degenerative AoV disease and secondary mitral insufficiency. A stable increase of VEGF and variations of endothelin without statistically significant difference suggest influence of ischemia on the local vascular blood supply. Decreased production of Il-1α together with moderate to rich production of Il-10, βD2, and βD3 indicates the dominance of the local immune system over inflammation.

One-year monitoring of nitrogen forms after the application of various types of biochar on different soils

Biochar is a carbon rich product obtained from pyrolysis of biomass. The use of biochar as soil amendment has been boosted in the last years due to its possible influence on fertility, including its potential ability to lower mineral nitrogen losses, but specially for its potential to reduce greenhouse gases and to increase carbon sequestration in soil. However, the studies on the effects of biochar on nitrogen forms in soil are heterogeneous and contradictory. The present work aims to clarify this point by applying 6 different biochars (with different origin and production process) on 6 different soils (of different properties). The amendment corresponded to an agronomic addition rate of 30 Mg ha−1, together with the addition of urea at a 100 kg N per ha rate. Then those mixtures were incubated for one year at a 60% of the WHC. The samples were analyzed for nitrogen forms (Kjeldahl-N, ammonium-N, nitrate-N, nitrite-N, and microbial-N) at different incubation times (1 week, 1 month, 4 months and 1 year after the addition). The results showed that the effects of different biochars on the soil nitrogen forms were variegated, mainly attributable to soil properties, and to a lesser extent to the particular biochar used. Overall, the Kjeldahl-N (KN) decreased after the incubation time, and only the mixtures with N-rich biochars achieved slightly higher KN compared to controls. Also, biochars tended to induce a decrease in NH4+-N, and, especially, in NO3–-N. The biochars causing highest shifts on N inorganic forms were those produced from agronomic sources (olive and corn wastes) and the one from pine wood materials subjected to high pyrolysis temperature conditions.

Processing of agricultural apple fruit waste into sugar rich feedstocks for the catalytic production of 5-HMF over a Sn Amberlyst-15 resin catalyst

In this study we considered processes of treatment of agricultural apple waste which is normally discarded. We show the effect of various pre-treatment procedures on the final catalytic performance to produce 5-HMF from this real world biomass waste. Our study of the various potential pre-treatment steps, and their effect on the catalytic performance, provides valuable new insights which can be used for the development of new processes for the localised small scale valorization of agricultural fruit waste. The apple waste is aimed to be converted into a sugar rich feedstock stream for the catalytic conversion to 5-hydroxymethyl furfural (5-HMF) at low temperatures (∼120°C). Filters with varying pore sizes were studied for the filtration of apple pomace after milling the rotten apples in order to reduce the solids content. The tested filters varied in pore sizes of 0.2μm, 2μm and 54μm. The effect of heating, acid or base treatment of the apple slurry was evaluated for increasing the speed of filtration. The highest flow rate was obtained for the filter with 54μm pores. The sugar rich filtrates were investigated in the catalytic conversion to 5-HMF over an easy-to-manufacture Sn exchanged resin (Amberlyst-15) catalyst. Results showed that filtrates obtained over a 2μm filter lead to the highest 5-HMF yields (18 %) without extra additives. Adjustment of the reaction mixtures to pH 7 resulted in a lower catalytic activity. 5-HMF is proposed to be extracted from the aqueous layer by using an organic liquid layer (methyl isobutyl ketone, MIBK). In order to increase the diffusion of 5-HMF to the MIBK layer the addition of salts to the reaction mixture was investigated. This leads to lower catalytic activity, possibly due to catalyst deactivation. Our results showed that a relatively wide pore filter (54μm) provides the fastest apple processing method and a filtrate reacting to the highest 5-HMF yield in catalytic conversion of the sugar rich product stream obtained from agricultural waste apples.

The impact of the Oakland SSB tax on prices and volume sold: A study of intended and unintended consequences.

We examine the effects of a sugar-sweetened beverage (SSB) tax that took effect in Oakland, California in 2017. Using rich customized universal product code -level data, we estimate the effect of the SSB tax on prices and volume in the short to medium term in a difference-in-differences framework. We pay particular attention to tax-avoidance strategies that may minimize the policy's intended effect including: (i) transfers to SSBs to the nontaxed border area (i.e., cross-border shopping), (ii) a move from high-priced per ounce single serve to their cheaper multipacks or larger format counterparts (i.e., format switching), and (iii) a move from high-priced beverages to less expensive ones within a category and format (i.e., brand switching). We find that the year-over-year tax pass-through is 49%. We find that volume sold of taxed beverages fell by 14%, but 46% of this decrease is offset with an increase in the border area. We also find evidence of substitution to lower-priced taxed beverages but no evidence of switching to cheaper formats. Finally, we find important dynamic effects with respect to tax pass-through, volume sold and cross-border shopping.

Invasion, Impact and Control Techniques for Invasive Ipomoea hildebrandtii on Maasai Steppe Rangelands

The ecosystem integrity of the Simanjiro Maasai steppe rangeland in Tanzania is threatened by the invasive plant Ipomoea hildebrandtii Vatke. However, its invasion status, impact and control techniques are unclear in the country. We conducted a study in Terrat and Sukuro villages in Simanjro District, Tanzania, to assess its invasion status and impact across grassland–woodland habitats using point sampling techniques. Key informant interviews and questionnaires were used to assess techniques used by the Maasai pastoralists to control I. hildebrandtii. A total of 10 plots (70 m2 each) with 9 quadrats (1 m2 each) in the invaded and non–invaded sites were established to study I. hildebrandtii invasions. The impact of I. hildebrandtii on rangelands was investigated by comparing herbage (herbaceous vegetation) species composition, richness, basal cover and biomass productivity between invaded and non–invaded plots. Results revealed that I. hildebrandtii invasion was higher in grass woodland habitats (90%) than in non-invaded plots. Non–invaded plots exhibited higher biomass productivity (0.289 ± 0.03 t DM/ha) than invaded plots (0.202 ± 0.02 t DM/ha). Furthermore, non–invaded plots had a higher basal cover (grasses: 54.71 ± 1.95%, forbs: 45.29 ± 1.95%) compared with invaded plots. We also recorded high native plants abundance in quadrats with low I. Hildebrandtii density (22.00 ± 1.36). Additionally, 81% of Maasai pastoralists reported to manually (uproot) control I. hildebrandtii. Based on the results of our study, we recommend further research and novel control techniques coupled with education to be implemented in the Simanjiro.

H2-rich syngas from glycerol dry reforming over Ni-based catalysts supported on alumina from aluminum dross

The performance of Ni-based catalyst supported on γ-Al2O3 for glycerol dry reforming (GDR) reaction was investigated in the current study. γ-Al2O3 was prepared from aluminum dross (AD) before use as catalyst support. Al2O3 was extracted using three different techniques assisted with ultrasonication: acid leaching with ammonia precipitation, acid leaching with re-precipitation of HCl, and alkaline leaching with ammonium hydrogen carbonate. The results show that extracted γ-Al2O3 3 (EGA3) with the highest purity and the surface area of 267.5 m2 g−1 was produced from acid leaching with ammonia precipitation technique at a calcination temperature of 800 °C. A series of Ni/EGA3 (5%, 10%, 15% and 20%) catalysts were tested and it was found that the catalytic activity was increased in the order of 5%Ni/EGA3 < 10%Ni/EGA3 < 20%Ni/EGA3 < 15%Ni/EGA3. 15%Ni/EGA3 catalyst has the highest catalytic activity due to the excellent distribution of Ni on the EGA support, high specific surface area of the support and high catalyst's basicity. In addition, the strong Ni-EGA3 interaction of the 15%Ni/EGA3 catalyst suppressed the carbon formation with the catalyst having the lowest carbon deposition value of 25.51% during the GDR reaction carried out for 8 h. Studies on the GDR reaction catalytic activities revealed that 15%Ni/EGA3 achieved the maximum catalytic activity with 56.7% glycerol conversion, 44.7% H2 yield, and 40.6% CO yield at 800 °C and CGR of 1:1. The H2:CO ratio obtained in this study was approximately 1.2–1.5 throughout the reaction, depicting a relatively rich H2 syngas product. Overall, the strong interaction between Ni and EGA3 ensured stable Ni particles that can mitigate carbon deposits, thereby enhancing the catalytic activity.

Hydrogen rich syngas production from sorption enhanced gasification of cellulose in the presence of calcium oxide

Sorption enhanced gasification of biomass is a novel technology for high purity H2 production and simultaneous carbon negative emission. The effect of CaO on the H2 production process was normally qualitatively explained. To quantitatively study the enhancing mechanism of CaO, the sorption enhanced gasification of cellulose for H2 rich syngas production was carried out in a fixed-bed pyrolysis-gasification system, the amount of CO2 absorbed, the carbon conversion rate of volatiles as well as the changes in the role of CaO under different gasification conditions were quantitatively studied. The results showed that CaO acted as a CO2 absorbent and/or a catalyst depending on the gasification temperature. It functioned as both a CO2 absorbent and a catalyst at lower temperatures of 550–700 °C, and a maximum amount of CO2 absorbed by CaO was achieved at 550 °C as 189.88 ml/g cellulose, CaO catalyzed the volatiles gasification to produce more H2 and achieve more sufficiently conversion with increasing temperature. While when the gasification temperature ≥750 °C, CaO acted only as a catalyst. The optimized condition for sorption enhanced pyrolysis-gasification of cellulose was of gasification temperature of 650 °C and of mass ratio of CaO/cellulose of ≥4, under which the actual carbon conversion rate of volatiles achieved ∼90 wt.%.

Temperature Fluctuation Attenuates the Effects of Warming in Estuarine Microbial Plankton Communities

Sea surface warming has the potential to alter the diversity, trophic organization and productivity of marine communities. However, it is unknown if temperature fluctuations that ecosystems naturally experience can alter the predicted impacts of warming. We address this uncertainty by exposing a natural marine plankton community to warming conditions (+3°C) under a constant vs. fluctuating (±3°C) temperature regime using an experimental mesocosm approach. We evaluated changes in stoichiometry, biomass, nutrient uptake, taxonomic composition, species richness and diversity, photosynthetic performance, and community metabolic balance. Overall, warming had a stronger impact than fluctuating temperature on all biological organization levels considered. As the ecological succession progressed toward post-bloom, the effects of warming on phytoplankton biomass, species richness, and net community productivity intensified, likely due to a stimulated microzooplankton grazing, and the community metabolic balance shifted toward a CO2 source. However, fluctuating temperatures reduced the negative effects of warming on photosynthetic performance and net community productivity by 40%. Our results demonstrate that temperature fluctuations may temper the negative effect of warming on marine net productivity. These findings highlight the need to consider short-term thermal fluctuations in experimental and modeling approaches because the use of constant warming conditions could lead to an overestimation of the real magnitude of climate change impacts on marine ecosystems.

The Association Between Obesity, Being Overweight and Socio-economic Status Among School-Age Children Living in Big Cities

Introduction: Obesity has become a serious health concern worldwide. Risk factors of obesity are different in urban and rural areas. The aim of this study was to determine the risk factors related to obesity and being overweight among children in low and high socio-economic groups in a big metropolitan city, Istanbul. Materials and Methods: A cross-sectional study was carried out on 490 schoolage children between 5 and 15 years. Low and high socio-economic groups were determined according to socio-economic status (SES). Socio-demographic characteristics of children were collected from the parents. Results: The effect of having frequent snacks rich in carbonhydrates (p=0,001) and sedentary lifestyles (p=0,001) on BMI was significant in both SES groups. In high SES group, BMI of the <10 years boys was significantly higher than that of the <10 years girls; Boys also had higher BMI at both age groups of either younger or older than 10 years. In low SES group, girls were significantly more overweight than boys. High family income, high paternal BMI and consuming energy rich products increased the obesity risk in children 1,560 times (OR: 1,560, %95 CI: 1,046-2,326), 2,015 times (OR: 2,015, %95 CI: 1,092-3,720), and 4,33 times (OR: 4,330, %95 CI: 2,897-6,472), respectively. Conclusions: As conclusion, high family income, high paternal BMI and consuming energy rich products incre-ased the obesity risk. We suggest that every community has own characteristics but boys tend to have high BMIs in families with high SES.

Platlet-Rich Plasma - Review of Literature.

Wound healing is a dynamic and physiological process for restoring the normal architecture and functionality of damaged tissue. Platelet-rich plasma (PRP) is an autologous whole blood product that contains a large number of platelets in a small volume of plasma with complete set of coagulation factors, which are in physiological concentrations. PRP has haemostatic, adhesive properties and acts supraphysiologically in the process of wound healing and osteogenesis. Platelets play a very important role in the wound healing process by providing growth factors that enhance the rate and quality of wound healing by many different mechanisms. The aim of this review is to describe: the biology of platelets and their role in the wound healing process, the terminology of platelet rich products, PRP preparation, activation and concentration of PRP, as well as the use of PRP in plastic surgery.

Development of technology vermicompost production for the coffee plant Industry

The aim of this study was to convert skin coffee (SC) amended with green waste (GW) and biochar(B) into vermicompost and evaluates their effects on the plant growth coffee. Biochar is a carbon rich product made from the rice husk pyrolysis process at 450°C, green waste eq branch cuttings and leaves from in the garden Universitas Negeri Jakarta and skin coffee from Cibulao coffee farm Bogor, Indonesia. Biochar was mixed with SC and GW in different proportion i.e., 6%,8% and 10% b along with control and allowed to pass through earthworm guts during two months. Vermicompost was characterization with SEM EDX and chemical content. The 8% biochar addition rate achieved maturity of vermicomposting and resulted in the highest quality vermicompost based on parameters such as organic C, C:N ratio, total N, P, K content and pH, were compared to a vermicompost as control. in the cultivation of plant growth, physiological parameters and morphology plant coffee growth such as number of leaf, heigh plant, steam diameter and shoot dried weight.

El proyecto holístico de Emma Kunz: cuando el arte se convierte en algo más

La artista suiza Emma Kunz (1892-1963) desarrolló una nutrida producción de patrones energéticos, que asumían una cercanía visual y simbólica con yantras y mandalas. Aunque no se han encontrado datos fehacientes al respecto, de acuerdo a la bibliografía consultada, así como a las aportaciones realizadas por el propio museo de la creadora, se cree que llegó a manejar la literatura alquímica de Paracelso y textos cristianos, así como fuentes escritas de escuelas herméticas. La gran mayoría de sus gráficos se elaboraron con objetivos terapéuticos, en la creencia de que emitían una onda de forma que podía afectar al paciente o espectador cuando se contemplaban.

Supercritical water gasification of wheat straw: Composition of reaction products and kinetic study

Supercritical water gasification (SCWG) technology is a potential technology to convert solid wastes to hydrogen rich gas products. But the gasification mechanism of real biomass in SCW is unclear due to its complicated composition and unique properties of SCW. In this paper, the gasification experiment of wheat straw in SCW was conducted in a quartz tube batch reactor, and the gasification properties was analyzed through researching the variation of gas yield, composition, liquid products and surface morphology of biochar to help understand the gasification mechanism. Besides, the reaction kinetic model of wheat straw was established to provide guidance for the acceleration of its gasification. The results illustrated that the increase of reaction time can enhance the gasification obviously (CGE increased by 37% as time extended from 1 min to 15 min) and temperature became the limitation factor after 15min. Higher temperature can increase the hydrogen yield obviously, which was raised by 7.2 mol/kg within 100 °C temperature increment, and the highest hydrogen yield was 12.88 mol/kg at 700 °C, 30 min. Kinetic study illustrated that the decomposition of PAHs was the rate-controlling step of wheat straw, activation energy of which was the highest, 427.13 kJ mol−1.

The role of sour and bitter perception in liking, familiarity and choice for phenol-rich plant-based foods

Among factors influencing food preferences and choices, individual differences in taste perception play a key role in defining eating behaviour. In particular, sour and bitter responsiveness could be associated with the acceptance and the consumption of phenol-rich plant-based foods recommended for a healthy diet. The aim of this study was to investigate, in a large population sample, the associations among sour and bitter responsiveness and liking, familiarity and choice for plant-based foods characterized by these target tastes. Adults aged 18 to 60 years (n = 1198; 58% women) were tested for their sour and bitter responsiveness both in water solutions and in food models (pear juice-based beverages modified in citric acid content to induce different levels of sourness: 0.5, 2.0, 4.0 and 8.0 g/kg; chocolate pudding samples modified in sucrose content to induce different levels of bitterness: 38, 83, 119, 233 g/kg). Familiarity, stated liking and choice for fruit juices and vegetables varying for sour/bitter taste (high in bitter/sour taste: e.g. grapefruit juice and cauliflower; low in bitter/sour taste: e.g. zucchini and pineapple juice) were measured. Results showed a significant positive correlation between bitter and sour taste perception in water solutions and model foods, as well as a positive correlation between the perceived intensity of the two taste stimuli. Subjects characterized by high responsiveness to the two target stimuli were found to give lower liking scores to foods characterized by sour/bitter tastes and tended to choose less sour/bitter foods compared to less responsive subjects.Thus, food choice for phenol rich plant-based products could be associated with a reduced responsiveness to bitter and sour tastes and a consequent higher acceptance of food products characterized by these taste qualities.

Island Colonization and Environmental Sustainability in the Postglacial Mediterranean

Island environments present challenges to human colonization, but we have a poor understanding of how environmental difference drives heterogeneous patterns of insular settlement. In this paper, we assess which environmental and geographic variables positively or negatively affect the long-term sustainability of human settlement on islands. Using the postglacial Mediterranean basin as a case study, we assess the impact of area, isolation index, species richness, and net primary productivity (NPP) on patterns of island occupation for both hunter-gatherer and agropastoral populations. We find that models involving area most effectively accounts for sustainability in hunter-gatherer island settlement. The agropastoral data are noisier, perhaps due to culturally specific factors responsible for the distribution of the data; nonetheless, we show that area and NPP exert profound influence over sustainability of agropastoral island settlement. We conclude by suggesting that this relates to the capacity of these variables to impact demographic robusticity directly.

Hydrogen rich products from waste HDPE/LDPE/PP/PET over Me/Ni-ZSM-5 catalysts combined with dolomite

This work focuses on the pyrolysis-gasification of real waste polymers in one stage tubular reactor with and without catalyst at 550 °C and 850 °C. Moreover, the possibility for dry reforming by in situ CO2 generation was also investigated using dolomite. To enhance the syngas production from waste plastics, Ni/ZSM-5 catalyst was synthetized by wet impregnation with 4.82% of Ni, then the catalyst was loaded by further elements in ~2% concentration (Ca, Ce, La, Mg, and Mn). The composition of gases and liquid products was measured by gas-chromatography, while the coke deposition on the spent catalysts was followed by temperature-programmed oxidation. It was found that a large amount of amorphous carbons was produced at 550 °C with Ni/ZSM-5 catalyst. The in-situ addition of the carbon-dioxide can enhance the production of syngas because both the hydrogen and carbon-monoxide concentration can drastically increase. Furthermore, the carbon deposition on the catalyst surface can be reduced by using dolomite. Based on the results of the various Me/Ni/ZSM-5 catalysts, the Ce/Ni/ZSM-5 was the most promising catalyst for the production of syngas (122.6 mmol/g at 850 °C). While, Mg/Ni/ZSM-5 showed less effect on the decomposition reaction, as low syngas yield was produced (62.8 mmol/g at 850 °C). The maximum yield of pyrolysis oil was achieved at 550 °C for the process without the catalyst.