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Effects of nano cotton stalk and palm leaf ashes on ultrahigh-performance concrete properties incorporating recycled concrete aggregates
No full textThe demand for partial replacement and complementary products of cement to enhance the properties of concrete and reduce the environmental pollution from the cement industry is recently increasing. Nano cotton stalk ash (NCSA) and palm leaf ash (PLA) are agricultural residues resulting from the burning of cotton stalk and palm leaves used as biomass. This investigation aims to study the effect of using NCSA and PLA as partial replacements to cement in ultrahigh-performance concrete (UHPC). As partial replacements for cement mass, 0%, 2.5%, 5, 7.5% and 10% of NCSA and 10%, 20% and 30% of PLA were adopted to produce the UHPC. Sixteen mixtures were prepared to evaluate the new and mechanical properties of UHPC containing the NCSA and the PLA. In addition, NCSA and PLA morphologies were evaluated using a scanning electron microscope, and thermogravimetric analysis with differential thermal analysis and X-ray diffraction was applied to assess ash characteristics. Results of the microstructure tests showed that heat treatment of the ash improved its properties by removing carbon and unburned organic matter with a slight change in the mineral composition of the PLA. The increase in the cement replacement rates by ashes led to a decrease in the slump flow, whilst the largest slump flow reduction was recorded in the mix containing 30% of PLA and 10% of NCSA as a replacement of Portland cement by 14.5% mm compared with the reference mix. The application of replacement rates by 2.5% and 5% of NCSA and 20% of PLA by cement mass to produce UHPC respectively realised the highest compressive strengths of 161.7 and 170.1 MPa at 90 days. Moreover, the mixture containing 20% of PLA with 5% of NCSA achieved the highest values of splitting tensile strength, flexural strength and elastic modulus.The demand for partial replacement and complementary products of cement to enhance the properties of concrete and reduce the environmental pollution from the cement industry is recently increasing. Nano cotton stalk ash (NCSA) and palm leaf ash (PLA) are agricultural residues resulting from the burning of cotton stalk and palm leaves used as biomass. This investigation aims to study the effect of using NCSA and PLA as partial replacements to cement in ultrahigh-performance concrete (UHPC). As partial replacements for cement mass, 0%, 2.5%, 5, 7.5% and 10% of NCSA and 10%, 20% and 30% of PLA were adopted to produce the UHPC. Sixteen mixtures were prepared to evaluate the new and mechanical properties of UHPC containing the NCSA and the PLA. In addition, NCSA and PLA morphologies were evaluated using a scanning electron microscope, and thermogravimetric analysis with differential thermal analysis and X-ray diffraction was applied to assess ash characteristics. Results of the microstructure tests showed that heat treatment of the ash improved its properties by removing carbon and unburned organic matter with a slight change in the mineral composition of the PLA. The increase in the cement replacement rates by ashes led to a decrease in the slump flow, whilst the largest slump flow reduction was recorded in the mix containing 30% of PLA and 10% of NCSA as a replacement of Portland cement by 14.5% mm compared with the reference mix. The application of replacement rates by 2.5% and 5% of NCSA and 20% of PLA by cement mass to produce UHPC respectively realised the highest compressive strengths of 161.7 and 170.1 MPa at 90 days. Moreover, the mixture containing 20% of PLA with 5% of NCSA achieved the highest values of splitting tensile strength, flexural strength and elastic modulus
Effect of high temperatures on mechanical, radiation attenuation and microstructure properties of heavyweight geopolymer concrete
No full textAbstract. Heavyweight geopolymer concrete (HWGC) is a new concrete type that combines the benefits of geopolymer concrete (GC) and heavyweight concrete. HWGC can be used to produce particular properties such as high radiation shielding, and mass concrete elements. HWGC based on fly ash and ground granulated blast furnace slag, using electric arc furnace steel slag (EAFSS), barite and ilmenite coarse aggregates can substantially have higher specific gravities than concrete made with crushed dolomite. In the experimental work carried out on four main groups, 13 GC mixes are prepared by using heavyweight coarse aggregates (HWCAs) at volume ratios of 0%, 25%, 50%, 75% and 100%. Fresh and mechanical properties, compressive and tensile strengths, and influence of high temperature on radiation are investigated for specimens subjected to high temperatures of up to 900°C for 1, 2 and 3 hours. Moreover, the internal structure of geopolymer is analyzed using scanning electron microscope and energy-dispersive X-ray. Results show a good effect of HWCAs on the properties, radiation shielding and unit weight. The density of heavyweight geopolymer mixes ranges between 2,415 and 3,480 kg/m3, and HWCA ratios contribute to an increase in all properties of GC mixtures using up to 75% of NWCAs. Heavier coarse aggregate of ilmenite dampens the effect of higher temperatures on GC strength compared with lighter aggregates. In addition, replacing crushed dolomite with heavyweight aggregates of EAFSS, barite and ilmenite increases the attenuation rate to 27%, 21% and 13%, respectively. This finding confirms that the type of aggregate used in the production of GC is important for reducing the permeability of X-ray.Abstract. Heavyweight geopolymer concrete (HWGC) is a new concrete type that combines the benefits of geopolymer concrete (GC) and heavyweight concrete. HWGC can be used to produce particular properties such as high radiation shielding, and mass concrete elements. HWGC based on fly ash and ground granulated blast furnace slag, using electric arc furnace steel slag (EAFSS), barite and ilmenite coarse aggregates can substantially have higher specific gravities than concrete made with crushed dolomite. In the experimental work carried out on four main groups, 13 GC mixes are prepared by using heavyweight coarse aggregates (HWCAs) at volume ratios of 0%, 25%, 50%, 75% and 100%. Fresh and mechanical properties, compressive and tensile strengths, and influence of high temperature on radiation are investigated for specimens subjected to high temperatures of up to 900°C for 1, 2 and 3 hours. Moreover, the internal structure of geopolymer is analyzed using scanning electron microscope and energy-dispersive X-ray. Results show a good effect of HWCAs on the properties, radiation shielding and unit weight. The density of heavyweight geopolymer mixes ranges between 2,415 and 3,480 kg/m3, and HWCA ratios contribute to an increase in all properties of GC mixtures using up to 75% of NWCAs. Heavier coarse aggregate of ilmenite dampens the effect of higher temperatures on GC strength compared with lighter aggregates. In addition, replacing crushed dolomite with heavyweight aggregates of EAFSS, barite and ilmenite increases the attenuation rate to 27%, 21% and 13%, respectively. This finding confirms that the type of aggregate used in the production of GC is important for reducing the permeability of X-ray
Influence of variation of structural parameters on magnetic properties of Al-substituted Ni spinel ferrite
Get PDFIt is very important to study the structural properties of the material to
understand the physical properties. According to suggested cations distribution
of Ni–Al ferrite as the formula ðFe3þ
1 tAl3þ
t Þ Ni2þAl3þ
x tFe3þ
1 xþt O2
4 , with
(0:0 x 0:5) and (0:0 t 0:1), the structural parameters were studied. The
cations radii of tetrahedral (RT) did not change, but octahedral (RO) sites
decreased with increasing Al3? ions. Lattice constants (ath) decreased with
increasing Al content. The values of u43m changed over the ranged 0.3818538155,
whereas the values of u3m varied from 0.25685 to 0.25655. With increasing Al
content, M–M lengths decreased, in addition, the bond lengths q, r, and s decreased
except p. In addition, with increasing Al3? ions, h1, h2, and h5 decreased
but h3 and h4 increased. dTE and dTL were constant, whereas dOEu, dOL; and dOE
decreased with increasing Al3? ions. LT T, LO O; and LT O reflected the same
behavior as that of ath, where they decreased with increasing Al3? ions concentration.
As a result, the incorporation of non-magnetic Al3? ions into the
given ferrite system reduces the strength of the magnetic interactions, which
relates to the changing on structural parameters.It is very important to study the structural properties of the material to
understand the physical properties. According to suggested cations distribution
of Ni–Al ferrite as the formula ðFe3þ
1 tAl3þ
t Þ Ni2þAl3þ
x tFe3þ
1 xþt O2
4 , with
(0:0 x 0:5) and (0:0 t 0:1), the structural parameters were studied. The
cations radii of tetrahedral (RT) did not change, but octahedral (RO) sites
decreased with increasing Al3? ions. Lattice constants (ath) decreased with
increasing Al content. The values of u43m changed over the ranged 0.3818538155,
whereas the values of u3m varied from 0.25685 to 0.25655. With increasing Al
content, M–M lengths decreased, in addition, the bond lengths q, r, and s decreased
except p. In addition, with increasing Al3? ions, h1, h2, and h5 decreased
but h3 and h4 increased. dTE and dTL were constant, whereas dOEu, dOL; and dOE
decreased with increasing Al3? ions. LT T, LO O; and LT O reflected the same
behavior as that of ath, where they decreased with increasing Al3? ions concentration.
As a result, the incorporation of non-magnetic Al3? ions into the
given ferrite system reduces the strength of the magnetic interactions, which
relates to the changing on structural parameters
Extended Signed Quadrature Spatial Modulation System With Multi-User Support
No full textSigned quadrature spatial modulation (SQSM) was recently introduced to enhance the throughput of spatial modulation (SM) in multiple-input multiple-output (MIMO) systems. This strategy involves independently transmitting the real and imaginary components of a symbol and its inverse from four independent antennas. In this paper, an extended SQSM (ESQSM) system is proposed. It combines K SQSM constellations and transmits them from the same transmit-antenna set with the aim of realizing a K-fold improvement in the spectral efficiency
(SE). The proposed ESQSM employs the average power of the K SQSM constellations as an additional dimension for transmission.
Performance of the proposed ESQSM surpasses that of other state-of-art SM systems such as the QSM, DSM, IQSM, SQSM, and EQSM by 13 dB, 11 dB, 10.55 dB, 10 dB, and 6.8 dB, respectively. In this paper, we also propose an efficient ESQSM with a multi-user (ESQSM-MU) system inspired by the ESQSM ability in increasing the SE. The proposed ESQSM-MU system offers a significant bit error rate (BER) improvement and a higher capacity (i.e., 5K-users) compared to the current non orthogonal multiple access-SM (NOMA-SM) and SM-assisted multi-antenna NOMA (SM-AMA-NOMA) systems. Moreover, an efficient low-complexity detector is introduced for the ESQSM signal detection, promising a 91.2% reduction in the computational complexity of ESQSM and ESQSM-MU systems relative to the maximum likelihood (ML) with a trivial loss in performance.This work was supported by the Research Council (TRC)
of the Sultanate of Oman, under Grant TRC/BFP/ASU/2018Signed quadrature spatial modulation (SQSM) was recently introduced to enhance the throughput of spatial modulation (SM) in multiple-input multiple-output (MIMO) systems. This strategy involves independently transmitting the real and imaginary components of a symbol and its inverse from four independent antennas. In this paper, an extended SQSM (ESQSM) system is proposed. It combines K SQSM constellations and transmits them from the same transmit-antenna set with the aim of realizing a K-fold improvement in the spectral efficiency
(SE). The proposed ESQSM employs the average power of the K SQSM constellations as an additional dimension for transmission.
Performance of the proposed ESQSM surpasses that of other state-of-art SM systems such as the QSM, DSM, IQSM, SQSM, and EQSM by 13 dB, 11 dB, 10.55 dB, 10 dB, and 6.8 dB, respectively. In this paper, we also propose an efficient ESQSM with a multi-user (ESQSM-MU) system inspired by the ESQSM ability in increasing the SE. The proposed ESQSM-MU system offers a significant bit error rate (BER) improvement and a higher capacity (i.e., 5K-users) compared to the current non orthogonal multiple access-SM (NOMA-SM) and SM-assisted multi-antenna NOMA (SM-AMA-NOMA) systems. Moreover, an efficient low-complexity detector is introduced for the ESQSM signal detection, promising a 91.2% reduction in the computational complexity of ESQSM and ESQSM-MU systems relative to the maximum likelihood (ML) with a trivial loss in performance
تأثير المجال المغناطيسي في نمو طفيل المُتَحَوِّلَة الحَالّة للنُسُج Entamoeba histolytica المعزولة من المرضى في فلسطين
No full textStatic magnetic field (SMF) is generated in vicinity of moving charge or current passing through conductor. In this study, we aimed to investigate the effect of SMF on the growth of the cultured Entamoeba histolytica (E. histolytica) trophozoites. Different SMF strengths with maximum value equals 30 mT (mT) was applied on the E.histolytica for different periods of times: 0 h, 24 h, 48 h, and 72 h. A modified diphasic liver infusion agar medium was used for culturing E. histolytica in vitro. The results showed the successful stabilization of culture of E. histolytica trophozoites. If we kept the sample for longer time, e. g. 14 days, the growth rate decreases to zero. When applying 10 mT and 15 mT SMF on the sample, it is found that the cultivated E. histolytica trophozoites dies after 4 and 2 days respectively. The experiments suggested that the SMF inhibited the growth and the propagation of E. histolytica cells. In addition, it completely killed all the cells in a short time interval which depend on the SMF strength. It is concluded that the SMFs inhibits the growth of E. histolytica and change the morphology of these cells. Thus, we recommend to use SMF as treatment to mitigate the growth of E. histolytica.يتم إنشاء المجال المغناطيسي الثابت (SMF) بالقرب من الشحنة المتحركة أو التيار الذي يمر عبر الموصل. في هذه الدراسة ، هدفنا إلى تقصي تأثير SMF على نمو الكائنات الحية المتحولة الحالة للنسج (E. histolytica) المزروعة. تم تطبيق قوى SMF مختلفة بقيمة قصوى تساوي 30 طن متري (طن متري) على E.histolytica لفترات زمنية مختلفة: 0 ساعة ، 24 ساعة ، 48 ساعة ، 72 ساعة. تم استخدام وسط أجار معدّل لتسريب الكبد ثنائي الطور لزراعة E. النسيجية في المختبر. وأظهرت النتائج نجاح استزراع جرثومة E.histolytica trophozoites. إذا احتفظنا بالعينة لفترة أطول ، ه. ز. 14 يومًا ، ينخفض معدل النمو إلى الصفر. عند تطبيق 10 ملي مولاري و 15 ملي طن من SMF على العينة ، وجد أن النواشط المزروعة من النوع E. histolytica المزروعة تموت بعد 4 و 2 أيام على التوالي. أشارت التجارب إلى أن SMF يثبط نمو وانتشار خلايا E. بالإضافة إلى ذلك ، قتل جميع الخلايا تمامًا في فترة زمنية قصيرة والتي تعتمد على قوة SMF. وخلص إلى أن SMFs يثبط نمو المتحولة الحالة للنسج وتغير شكل هذه الخلايا. وبالتالي ، نوصي باستخدام SMF كعلاج للتخفيف من نمو E
المثاليات المفرطة البدائية على حلقات مفرطة ضربية
No full textAbstract In this paper, we introduce the concepts of adjoint, n-adjoint of a hyperideals and primal and n-primly hyperideals of a commutative multiplicative hyperrings. Many results con- cerning prime, n-primly, primary and primal hyperideals of a commutative multiplicative hy- perrings are given, illustrated by several examples. Also we characterise all prime, primary, n-primly and primal Cu hyperideals of quotient hyperring.الملخص في هذا البحث ، نقدم مفاهيم معايرة ، n- مساعدة من hyperideals البدائية و n-primly hyperideals من التبادلية الضرب المفرط. تم تقديم العديد من النتائج المتعلقة بالعلامات الزائدة الأولية والبدائية والبدائية للهيكل التبادلي المضاعف ، موضحة بعدة أمثلة. كما أننا نميز جميع الصفات الأولية للنحاس الأولية والأولية والبدائية والبدائية لفرط حاصل القسمة
Cognitive behavior therapy for low self esteem randomized controlled trial in a psychiatric hospital in Gaza Strip
No full text"Background: Substance use disorders (SUDs) are a serious threat to health and society; Focusing
on improving the self-esteem of substance users through the Cognitive Behavioral Therapy (CBT)
program is an important factor in addiction treatment.
Objectives: The study aims to evaluate the effectiveness of CBT in improving self-esteem among
patients with SUBs in the Gaza Strip.
Methods: The experimental design was used, 30 male Participants were divided randomly into two
groups: experimental and control (n = 15) per group. Both groups received the standard treatment,
while only the experimental group underwent the CBT program consisting of (16) sessions over 2
months. All of the subjects completed a self-esteem questionnaire before and after the intervention,
and 2 months later (follow-up). The required data were collected and analyzed.
Results: a statistically significant difference between the two groups in favor of the experimental
group in the level of self-esteem was found. There are statistically significant differences between
the mean scores of the experimental group regarding the post and follow-up measurements on the
self-esteem scale after 2 months, p < .05 in self-esteem in posttest and follow-up measurement.
Results indicated that CBT was effective in improving self-esteem among patients with SUDs.
Conclusions: The study concludes that CBT sessions have been effective and successful in
improving self-esteem among patients with SUD""Background: Substance use disorders (SUDs) are a serious threat to health and society; Focusing
on improving the self-esteem of substance users through the Cognitive Behavioral Therapy (CBT)
program is an important factor in addiction treatment.
Objectives: The study aims to evaluate the effectiveness of CBT in improving self-esteem among
patients with SUBs in the Gaza Strip.
Methods: The experimental design was used, 30 male Participants were divided randomly into two
groups: experimental and control (n = 15) per group. Both groups received the standard treatment,
while only the experimental group underwent the CBT program consisting of (16) sessions over 2
months. All of the subjects completed a self-esteem questionnaire before and after the intervention,
and 2 months later (follow-up). The required data were collected and analyzed.
Results: a statistically significant difference between the two groups in favor of the experimental
group in the level of self-esteem was found. There are statistically significant differences between
the mean scores of the experimental group regarding the post and follow-up measurements on the
self-esteem scale after 2 months, p < .05 in self-esteem in posttest and follow-up measurement.
Results indicated that CBT was effective in improving self-esteem among patients with SUDs.
Conclusions: The study concludes that CBT sessions have been effective and successful in
improving self-esteem among patients with SUD
Dispersion properties of slab waveguides with a linear graded-index film and a nonlinear substrate
No full text"
Three-layer slab waveguide with a graded-index film and a nonlinear substrate is investigated. The nonlinear substrate is
considered of Kerr-type and the film index is assumed to change linearly as we move from the film-clad to the film-
substrate interfaces. The solutions of the fields in the guiding film contains Airy functions which can be written as Bessel
functions of order 1/3. The dispersion relation is derived in terms of three well-known normalized parameters V, a and
b and the dispersion properties are plotted and studied. Many interesting features are obtained such as the nonexistence of
cut-off thickness due to the nonlinear substrate and the value of the normalized guide index does not exceed unity which
means they correspond to guided modes.""
Three-layer slab waveguide with a graded-index film and a nonlinear substrate is investigated. The nonlinear substrate is
considered of Kerr-type and the film index is assumed to change linearly as we move from the film-clad to the film-
substrate interfaces. The solutions of the fields in the guiding film contains Airy functions which can be written as Bessel
functions of order 1/3. The dispersion relation is derived in terms of three well-known normalized parameters V, a and
b and the dispersion properties are plotted and studied. Many interesting features are obtained such as the nonexistence of
cut-off thickness due to the nonlinear substrate and the value of the normalized guide index does not exceed unity which
means they correspond to guided modes.
An ultra-high birefringent and nonlinear decahedron photonic crystal fiber employing molybdenum disulphide (MoS2): A numerical analysis
No full text"A novel Decahedron photonic crystal fiber (DHn-PCF) is proposed. To sustain high birefringence and nonline-
arity, the central elliptical core is filled with a highly nonlinear 2D material molybdenum disulphide (MoS2). The
significant performance parameters of the proposed DHn-PCF like birefringence, nonlinearity, confinement loss,
and core power fraction has been investigated with change in its structural parameters. Simulation results
confirmed an exceptionally high birefringence and nonlinearity of 0.632 and 9.68 × 105 W− 1 Km− 1 with the
outstanding core power fraction of 98.6% for the well-known communication window at 1.55μm. Besides, the
effective material loss (EML) and confinement loss (CL) are also found very low as 0.0302cm− 1 and 8.7 ×
10− 10dB/mfor the same communication window. Therefore, with all these excellent outcomes, the proposed
DHn-PCF proves itself a potential candidate for polarization maintenance, residual polarization compensation,
dispersion compensator, bio-medical imaging, supercontinuum and solitons generation, high bit data rate tele-
communication and sensing application.""A novel Decahedron photonic crystal fiber (DHn-PCF) is proposed. To sustain high birefringence and nonline-
arity, the central elliptical core is filled with a highly nonlinear 2D material molybdenum disulphide (MoS2). The
significant performance parameters of the proposed DHn-PCF like birefringence, nonlinearity, confinement loss,
and core power fraction has been investigated with change in its structural parameters. Simulation results
confirmed an exceptionally high birefringence and nonlinearity of 0.632 and 9.68 × 105 W− 1 Km− 1 with the
outstanding core power fraction of 98.6% for the well-known communication window at 1.55μm. Besides, the
effective material loss (EML) and confinement loss (CL) are also found very low as 0.0302cm− 1 and 8.7 ×
10− 10dB/mfor the same communication window. Therefore, with all these excellent outcomes, the proposed
DHn-PCF proves itself a potential candidate for polarization maintenance, residual polarization compensation,
dispersion compensator, bio-medical imaging, supercontinuum and solitons generation, high bit data rate tele-
communication and sensing application.
Surface plasmon resonance-based optical sensor using a thin layer of plasma
No full text"We propose a surface plasmon resonance (SPR) biosensor that consists of six layers: glass prism (SF 10), chromium,
metal, molybdenum disulphide, graphene, and sensing medium. A seventh layer is added between the glass prism
and the chromium layer, which is a gap filled with plasma as a dielectric material. The plasma layer is expected
to carry the amenity of the graphene optical characteristics and absorption ability. It is also expected to improve
sensitivity of the SPR structure. The numerical calculations show that the sensitivity of the sensor is 76.11 deg/RIU
(refractive index unit); without the plasma layer, it can be improved to 103 deg/RIU in the presence of 25 and 35 nm
thick plasma and silver layers, respectively. The structure parameters are optimized with respect to the sensitivity.
The proposed sensor can potentially be used for biological purposes.""We propose a surface plasmon resonance (SPR) biosensor that consists of six layers: glass prism (SF 10), chromium,
metal, molybdenum disulphide, graphene, and sensing medium. A seventh layer is added between the glass prism
and the chromium layer, which is a gap filled with plasma as a dielectric material. The plasma layer is expected
to carry the amenity of the graphene optical characteristics and absorption ability. It is also expected to improve
sensitivity of the SPR structure. The numerical calculations show that the sensitivity of the sensor is 76.11 deg/RIU
(refractive index unit); without the plasma layer, it can be improved to 103 deg/RIU in the presence of 25 and 35 nm
thick plasma and silver layers, respectively. The structure parameters are optimized with respect to the sensitivity.
The proposed sensor can potentially be used for biological purposes.