Scale-up studies for stable,long-term indoor and outdoor production of hydrogen by immobilized Rhodobacter capsulatus

Photofermentative hydrogen production by immobilized Rhodobacter capsulatus YO3 was carried out in a novel photobioreactor in sequential batch mode under indoor and outdoor conditions. Long-term H₂ production was realized in a 1.4 L photobioreactor for 64 days using Rhodobacter capsulatus YO3 immobilized with 4% (w/v) agar on 5 mM sucrose and 4 mM glutamate. The highest hydrogen yield (19 mol H₂/mol sucrose) and hydrogen productivity (0.73 mmol H₂ L^?1 h^?1) were achieved indoors on 5 mM sucrose. The effect of initial sucrose concentration (5 mM, 10 mM, and 20 mM) on hydrogen production was also investigated. Sustained hydrogen production was carried out under natural, outdoor conditions as well. For the outdoor experiments, the highest hydrogen productivity and yield were obtained as 0.87 ± 0.06 mmol H₂ L^?1 h^?1 and 6.1 ± 0.2 mol H₂/mol sucrose, respectively on 10 mM sucrose. Furthermore, this system prevented sudden pH drops and fluctuations caused by the utilization of sucrose throughout the process. These results demonstrate that a proper immobilization setup can lead to long-term efficient and robust hydrogen production even under naturally varying conditions.     

The reconstruction of housing in Palestine 1993–2000: a case study from the Gaza Strip

In the Palestinian Territories, housing is thought to be amongst the most difficult problems facing the National Authority (PNA) (Al‐Agha, 1997 Al‐Agha Z (1997) A national outlook for housing in Palestine in: A. B. Zahlan (Ed.) Reconstruction of Palestine, Urban and Rural Development (London, Kegan Paul)  [Google Scholar], p. 3). Increased Israeli settlements, the large size of Palestinian families, the deteriorating economic situation, the lack of national banks operating in the field of housing, the presence of refugee settlements containing over 1.2 million people, the Israeli state's policy of residential demolition and land confiscation have all combined to present a severe obstacle to urban reconstruction in the region. In an attempt to address these issues and to make some progress towards realising the estimated 180 000 housing units required by the Palestinian people, the Palestinian Housing Council (PHC) was established in 1992 (Abd Alhadi, 1994 Abd Alhadi, R (1994) Construction and Housing in the West Bank and (Gaza) Strip (Geneva, United Nations Commission on Trade and Development)  [Google Scholar]; Ziara, 1997 Ziara M (1997) The Palestinian Ministry of Housing. Challenging and opportunities in A. B. Zahlan (ed.) Reconstruction of Palestine, Urban and Rural Development (London, Kegan Paul)  [Google Scholar]). Although it has had some success, the organisation has been plagued by reports of internal dissent and disputes with its beneficiaries. This paper seeks to cast some light on these controversies by focusing on the PHC's role in the Elkarama Housing Project in the Gaza Strip during the period 1993 to 2000.1 Here it must be emphasised that this paper does not claim to provide an analysis of the current situation in Gaza. The authors acknowledge that conditions in Palestine are extremely fluid and have, to a great degree, overtaken the issues considered above. In examining this rapidly‐evolving environment, however, it is valuable to reflect upon recent changes and, while recognising the acute systemic problems that Palestinian administrators face, to offer critical assessments of domestic policy decisions and their outcome. View all notes It will first outline the broader context in which public institutions within the Gaza Strip operate before offering an account of the structure and background of the PHC. It will then consider Elkarama itself and will conclude by summing up the various factors that have determined the project's outcome. Finally, the paper will offer some tentative recommendations for improved housing provisions within the Gaza Strip in the future.     

Biological hydrogen production from sugar beet molasses by agar immobilized R. capsulatus in a panel photobioreactor

Biohydrogen production from sugar beet molasses was investigated by using agar immobilized R. capsulatus YO3. A panel photobioreactor (1.4 L) was employed for a long-term hydrogen production in both indoor and outdoor conditions. The impact of several initial molasses concentrations on hydrogen production, yield and productivity were assessed. Indoor studies revealed that initial sucrose concentration in molasses should be kept below 20 mM to prevent inhibition of hydrogen production. The highest hydrogen productivity of 0.64 ± 0.06 mmol H₂ L^?1 h^?1 and yield of 12.2 ± 1.5 mol H₂/mol sucrose were obtained in indoors throughout 20 days of operation. For outdoors, hydrogen production continued for 40 days including consecutive 10 rounds under natural outdoor conditions. In outdoor conditions, the maximum hydrogen productivity and yield were 0.79 ± 0.04 mmol H₂ L^?1 h^?1 and 5.2 ± 0.4 mol H₂/mol sucrose respectively. These results indicate that the proposed system is promising for biohydrogen production from molasses at large-scale natural conditions.     

RS Codes with Filtered-OFDM: A Waveform Contender for 5G Mobile Communication Systems

In recent years, the proportion of elderly population in various countries has gradually increased. Increasing with age, it can entail illness. When these diseases are sudden, the elderly often die because there is no immediate treatment. Elderly care has become an important issue. According to this issue, we want to monitor the physiological data of the elderly, such as heartbeat, blood pressure, etc., through wearable devices. Once an abnormal condition is detected, the wearable device can be used to immediately request treatment from a nearby clinic or hospital. In order to improve the network quality of this service, we use the architecture of the mobile edge computing. The mobile edge computing provides features such as immediacy, low latency, proximity etc. However, the process of data transmission on the mobile edge computing has the risk of being stolen and identity authentication is also an important issue. Therefore, we propose a secure protocol based on cryptography to protect personal information with lightweight authentication. The proposed scheme aims to achieve mutual authentication, non-repudiation, integrity, user privacy, and defend against known attacks.