Applications of natural zeolites on agriculture and food production

Zeolites are crystalline hydrated aluminosilicates with remarkable physical and chemical properties, which include losing and receiving water in a reverse way, adsorbing molecules that act as molecular sieves, and replacing their constituent cations without structural change. The commercial production of natural zeolites has accelerated during the last 50 years. The Structure Commission of the International Zeolite Association recorded more than 200 zeolites, which currently include more than 40 naturally occurring zeolites. Recent findings have supported their role in stored‐pest management as inert dust applications, pesticide and fertilizer carriers, soil amendments, animal feed additives, mycotoxin binders and food packaging materials. There are many advantages of inert dust application, including low cost, non‐neurotoxic action, low mammalian toxicity and safety for human consumption. The latest consumer trends and government protocols have shifted toward organic origin materials to replace synthetic chemical products. In the present review, we summarize most of the main uses of zeolites in food and agruculture, along with the with specific paradigms that illustrate their important role. © 2017 Society of Chemical Industry     

Mobile phone based SCADA for industrial automation

SCADA is the acronym for "Supervisory Control And Data Acquisition." SCADA systems are widely used in industry for supervisory control and data acquisition of industrial processes. Conventional SCADA systems use PC, notebook, thin client, and PDA as a client. In this paper, a Java-enabled mobile phone has been used as a client in a sample SCADA application in order to display and supervise the position of a sample prototype crane. The paper presents an actual implementation of the on-line controlling of the prototype crane via mobile phone. The wireless communication between the mobile phone and the SCADA server is performed by means of a base station via general packet radio service (GPRS) and wireless application protocol (WAP). Test results have indicated that the mobile phone based SCADA integration using the GPRS or WAP transfer scheme could enhance the performance of the crane in a day without causing an increase in the response times of SCADA functions. The operator can visualize and modify the plant parameters using his mobile phone, without reaching the site. In this way maintenance costs are reduced and productivity is increased.     

Effect of reinforcement surface functionalization on the mechanical properties of nacre-like bulk lamellar composites processed by a hybrid conventional method

Alumina platelet reinforced epoxy matrix composites with an architecture resembling to natural nacre were fabricated by a hybrid conventional method called Hot-press Assisted Slip Casting process (HASC). Correlation between processing parameters, platelet content, platelet orientation and mechanical property enhancement of the fabricated composites was examined. In order to investigate the effect of interfacial compatibility and bonding on the mechanical properties of the fabricated inorganic–organic composites, platelet surfaces were modified with both epoxy- and amino-functional silanes. As received and functionalized platelet surfaces were studied by X-Ray Photoelectron Spectroscopy (XPS) to confirm the success of surface modification. Fabricated bio-inspired bulk lamellar composite materials were characterized in terms of their microstructural architecture and mechanical properties. The results obtained indicated that HASC processed composites exhibit enhanced flexural strength, stiffness and hardness, as compared to neat epoxy and composites fabricated by simple mixing, as a result of their nacre-like architecture with well aligned platelets. It has been also observed that functionalization by both type of silanes improves interfacial adhesion between platelets and epoxy matrix resulting in further enhancement of the mechanical properties of bulk lamellar composites fabricated by HASC.     

Desmoid tumours in familial adenomatous polyposis

Desmoids are rare, benign fibromatous lesions, which can arise in patients with familial adenomatous polyposis (FAP), a disorder caused by germline adenomatous polyposis coli (APC) gene mutation. This study investigated the risk of desmoids in FAP, the relation between specific APC gene mutations and desmoid formation, and the clinical characteristics of FAP patients with desmoids. Eighty three of 825 FAP patients (10%) from 49 of 161 kindreds (30%) had desmoids. The absolute risk of desmoids in FAP patients was 2.56/1000 person years; comparative risk was 852 times the general population. APC gene mutations were similar in families with and without desmoids. The female/male ratio was 1.4 (p = NS). Previous abdominal surgery was noted in 68% of patients with abdominal desmoids (55% developed within five years postoperatively). Desmoid risk in FAP family members of a desmoid patient was 25% in first degree relatives v 8% in third degree relatives. Desmoids are a comparatively common complication of FAP associated with surgical trauma and familial aggregation. Desmoid development was not linked to specific APC gene mutations and was not found predominantly in women. Studies of chemopreventive therapy, given within five years after abdominal surgery, should be considered in FAP patients with a family history of desmoid disease.     

Performance comparison of a single and multiband power amplifiers using IHP 0.25 μm SIGe HBT technology

In this work, a single‐band power amplifier (PA) with a fixed‐frequency/band output matching network and multiband PA with a switch‐tuned output matching network is designed, using IHP (Innovations for High Performance), 0.25 μm‐SiGe HBT process. The behavior of the amplifiers has been optimized for 2.4 GHz (WLAN), 3.6 GHz (UWB‐WiMAX), and 5.4 GHz (WLAN) frequency bands for a higher 1‐dB compression point and efficiency. Multiband characteristics of the amplifier were obtained by using a MOS‐based switching network. Two MOS switches were used for tuning the band of the output matching network. Postlayout simulations of the multiband‐PA provided the following performance parameters: 1‐dB compression point of 25.2 dBm, gain value of 36 dB, efficiency value of 12.8% operation and maximum output power of 26.8 dBm for the 2.4 GHz WLAN band, 1‐dB compression point of 25.5 dBm, gain value of 32 dB, efficiency value of 13.3% and maximum output power of 26.6 dBm for the 3.6 GHz UWB‐WiMAX band and 1‐dB compression point of 24.8 dBm, gain value of 23 dB, efficiency value of 12.5% and maximum output power of 26.3 dBm for the 5.4 GHz WLAN band. For the fixed‐band, at 3.6 GHz, the postlayout simulations resulted the following parameters: 1‐dB compression point of 25.5 dBm, gain value of 32 dB, efficiency value of 18% and maximum output power value of 26.8 dBm. Measurement results of the single‐band PA provided the following performance parameters: 1‐dB compression point of 20.5 dBm, gain value of 23 dB and efficiency value of 7% operation for the 2.4 GHz band; 1‐dB compression point of 25.5 dBm, gain value of 31.5 dB and efficiency value of 17.5% for the 3.6 GHz band; 1‐dB compression point of 22.4 dBm, gain value of 24.4 dB and efficiency value of 9.5% for the 5.4 GHz band. Measurement results show that using multistage topologies and implementing each parasitic as part of the matching network component has provided a wider‐band operation with higher output power levels, above 25 dBm, with SiGe:C process. These results proved that the PA, with switching/tunable output matching network, provides compatible performance parameters, when compared with the fixed‐band PA. The ability of being capable of operation in different frequency bands with compatible performance parameters, when compared with fixed‐band PA, multiband PA can be realized with additional less parasitics, area, and cost advantages. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.     

A PECVD diamond device for chemical gas sensing applications

This paper presents a new diamond based microelectronic gas sensor for applications that require operation at a higher and wider temperature range and in harsh environments such as process control, exhaust emission and engine monitoring. The CO gas sensing performance and detection mechanism of the new sensor have been studied by using I–V and I–t characteristics as a function of gas concentration over a wide temperature range (50–500 °C). The gas sensitivity of the sensor is high, repeatable and reproducible. The response time is in seconds to a small concentration of CO gas. Gas detection mechanism of the new sensor is attributed to the modification of the oxygen vacancies in the SnO_x layer through the reduction reaction between pre-adsorbed oxygen and CO gases.     

Dynamic resource scheduling schemes for W-CDMA systems

W-CDMA is the strongest candidate for the air interface technology of third-generation wireless communication systems. Dynamic resource scheduling is proposed as a framework that will provide QoS provisioning for multimedia traffic in W-CDMA systems. The DRS framework monitors the traffic variations and adjusts the transmission powers of users in an optimal manner to accommodate different service classes efficiently. Variable and optimal power allocation is suggested to provision error requirements and maximize capacity, while prioritized queuing is introduced to provision delay bounds. A family of DRS algorithms has been devised along these dimensions for obtaining different levels of QoS. The DRS schemes are discussed in terms of queuing and bandwidth allocation with an emphasis on their impact on delay QoS     

Design of a 4.2–5.4 GHz differential LC VCO using 0.35 μm SiGe BiCMOS technology for IEEE 802.11a applications

In this paper, a 4.2–5.4 GHz, ?Gm LC voltage controlled oscillator (VCO) for IEEE 802.11a standard is presented. The circuit is designed with AMS 0.35 μm SiGe BiCMOS process that includes high‐speed SiGe Heterojunction Bipolar Transistors (HBTs). According to post‐layout simulation results, phase noise is ?110.7 dBc/Hz at 1 MHz offset from 5.4 GHz carrier frequency and ?113.4 dBc/Hz from 4.2 GHz carrier frequency. A linear, 1200 MHz tuning range is obtained from the simulations, utilizing accumulation‐mode varactors. Phase noise was also found to be relatively low because of taking advantage of differential tuning concept. Output power of the fundamental frequency changes between 4.8 dBm and 5.5 dBm depending on the tuning voltage. Based on the simulation results, the circuit draws 2 mA without buffers and 14.5 mA from 2.5 V supply including buffer circuits leading to a total power dissipation of 36.25 mW. The circuit layout occupies an area of 0.6 mm² on Si substrate, including DC and RF pads. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007.     

The effects of diets containing different levels of common vetch (Vicia sativa) seed on fattening performance,carcass and meat quality characteristics of Awassi male lambs

The experiment was carried out to evaluate the effect of common vetch seed (CVS), used at various levels (0, 15 and 25%), as a protein source in diets replacing different proportion of barley, wheat bran and soybean meal on fattening performance, carcass and meat quality characteristics of Awassi male lambs at approximately 8 months of age. The lambs were divided into three treatment groups, T1 (control, fed a diet without CVS; n = 12), T2 (15% CVS; n = 12) and T3 (25% CVS; n = 12), at the beginning of the fattening period. The T2 and T3 lambs were fed with a concentrate including 15 and 25% of ground CVS. The main protein source was soybean meal in T1 diet treatment, partially replaced by vetch in T2 and T3 diet treatments. All groups were fed a diet consisting of concentrate mixture offered ad libitum, and 300 g of grass hay per lamb per day during the 60 day fattening period. Daily feed intake, daily weight gain and feed conversion efficiency (concentrate and hay consumption for 1 kg of live weight gain) were 1.716 kg, 0.26 kg and 6.60 for T1, 1.756 kg, 0.28 kg and 6.27 for T2 and 1.806 kg, 0.29 kg and 6.23 for T3, respectively. Growth, carcass and meat quality traits were almost the same across the groups. In conclusion, CVS supplementation to diets of Awassi lambs at a 0, 15 and 25% rates showed no statistical differences in fattening performance, wholesale cuts of carcasses, meat color parameters (L* = lightness, a* = redness, b* = yellowness, H = huge angle and C = chroma) and pH values, but there were numerical differences (improvement) in feed conversion efficiency. Copyright © 2005 Society of Chemical Industry