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Diamond-doped Silica Aerogels for Solar Geoengineering
Get PDFPh. D. Thesis.Geoengineering includes many techniques aimed to fight the global warming, which is one of
the biggest problems today. Even though aerosol injection into stratosphere is one of the most
promising solar geoengineering techniques, sulfate aerosols, which are suggested for such an
application, show significant drawbacks such as infrared (IR) absorption and ozone
degradation. Here, a novel composite material comprised of diamonds dispersed in a silica
aerogel network is investigated and compared to pure silica aerogel. Silica aerogels are
ultralight, highly porous, transparent and can host particles, while fulfilling particle size
limitation in terms of potential health risks for humans during respiration. In theoretical
models, diamond particles with high refractive index (~ 2.41) showed outstanding upscattering among other materials, without IR absorption. Moreover, in recent years, the lowcost production of silica aerogels suitable for large scale production has been developed and
diamond powders can be purchased at low cost in ton quantities.
Before doping of the silica aerogels, diamond part of the composite was studied since the
diamond is outstanding light scatterer and also for future applications of the diamond
particles. Two types of diamond particles were used: high pressure high temperature (HPHT)
microdiamonds (~ 500 nm in size) and detonation nanodiamonds (DNDs) (~ 3 nm in size). Raw
HPHT microdiamonds were treated with 1-undecene and zirconia beads and nuclear magnetic
resonance (NMR) and Fourier-transform infrared (FTIR) spectroscopy were used to detect the
alkyl groups on the surface of the treated HPHT microdiamonds. Both HPHT microdiamonds
were free of graphitic sp2
carbon (Raman scattering). Nanodiamond colloids, original 4 wt%
(as purchased) and diluted 1 wt%, were studied in terms of Zeta potential, pH and dynamic
light scattering (DLS) measurements to assess the stability of nanoparticles. The results
suggest that nanodiamond colloids are not stable in air or after dilution as the particles tend
to agglomerate.
Both micro- and nanodiamonds were added to tetraethoxysilane (TEOS)-based silica aerogels.
In case of microdiamonds, concentrations of 500, 700 and 900 ppm of diamond particles in
the precursor sol before gelation were used. It was observed that the higher the diamond
concentration in the sol, the final aerogel contained more wt% of diamond, with the maximum
concentration of ~ 3.3 wt% according to X-ray diffraction (XRD). The nanodiamond-doped
silica aerogel contained ~ 7.5 wt% of diamond in the final aerogel. It is suggested that the small
size of the nanodiamond particles allowed them to incorporate well in the aerogel network
and not to be washed away during solvent exchange step. Furthermore, aerogel with
nanodiamonds increased the surface area compared to the both pure aerogel and
microdiamond-doped silica aerogel, possible due to similar size of diamond to silica particles
that did not disturb the gelation of silica. Although DNDs are not suitable for solar scattering
due to graphitic sp2
carbon, DNDs were used in order to study the doping of aerogels with
diamonds. Additionally, scanning electron microscopy (SEM) and transmission electron
microscopy (TEM) were used to observe the porous aerogel formation and doping with
diamond particles.
The ultraviolet (UV)/Visible (Vis)/Near infrared (NIR) diffuse reflectance showed that
composite microdiamond-doped silica aerogel has an improved reflectance compared to
microdiamond powder or pure silica alone. The fall speed was calculated to estimate how long
the measured materials would stay in the atmosphere before sedimentation. The obtained
results are promising and could stimulate further in-depth studies with similar materials with
a potential for applications in solar geoengineeringEPSR
The future of learning: implementation of SOLE in a Saudi primary school
Get PDFPhD ThesisOver the last three decades, increased attention has been given to different forms of computer supported collaborative learning within the classroom. One such example is Self-Organised Learning Environments (SOLEs), in which students are supposed to work collaboratively using the Internet to answer a question with minimum teacher intervention. A number of empirical studies have indicated the effectiveness of using SOLE to improve learners’ academic performance when working in small cooperative groups. However, there have been no previous studies conducted in Saudi Arabia or even the Arab world in general, where SOLE is considered to be a new teaching and learning approach. This study is therefore a pioneer in the education field in Saudi Arabia that attempts to improve the traditional patterns of teaching in Saudi primary schools through introducing a new method and exploiting new sources of learning and specifically the Internet. The study also seeks to highlight the barriers in the face of introducing and implementing such methods to draw the attention of policymakers in Saudi Arabia in order to avoid them.
The current study has adopted an action research approach as a methodology through exposing a group of 28 primary school children in Riyadh city in Saudi Arabia to 10 SOLEs sessions over a period of 14 weeks. During these sessions, the participants’ activities were observed and their perceptions were surveyed. More specifically, students’ academic and social behaviour were observed and their opinions about learning within SOLE and how it compares to traditional classroom experience were surveyed. In addition, the parents of these children, their classroom teacher, the school head teacher and 17 other teachers from the same school were either surveyed or interviewed to explore opinions about SOLEs, perceptions of the participating pupils about SOLEs experience, and the challenges that might face introducing SOLEs into Saudi schools.
The findings indicate that engaging in SOLEs benefited students academically and socially. However, teamwork faced challenges as the students were internally dissatisfied with the role of an individual, equity and involvement in the group and they could not manage their interactions. Based on this, it is argued that more time seems required to achieve adequate social skills by students coming from traditional environment classrooms such as in Saudi Arabia, but teacher intervention might save time in this respect through facilitating group work and speeding up the acquisition of collaborative skills. Moreover, the results of this study revealed a number of challenges for integrating digital-technology-based learning such as SOLEs in Saudi schools. These challenges are the lack of students’ skills in working in a collaborative learning setting, the lack of resources (computers and Internet connection) and technical support and the lack of school time due to dense curriculum and high teacher workload. In addition, there is a deficiency in teacher training and specifically about how to integrate innovation teaching approaches in current curriculum effectively.
The study concludes with a discussion of the implications for researchers, practitioners and educational policy, and recommendations for further research. Despite the challenges, the study concurs with the value of the SOLEs approach as a realistic and effective method to help the Ministry of Education in Saudi Arabia to achieve the 2030 Kingdom’s vision
Monitoring and modelling antibiotic resistance in Southeast Asian rivers
Get PDFPhD ThesisPinpointing environmental antibiotic resistance (AR) hotspots in rivers in low-and-middle income countries (LMICs) is hindered by a lack of available and comparable
AR monitoring data relevant to such settings. Addressing this problem, a
comprehensive spatial and seasonal assessment of water quality and AR conditions
in a Malaysian river catchment was preformed to identify potential 'simple' surrogates
that mirror elevated AR. This included screening for β-lactam resistant coliforms, 22
antibiotics, 287 AR genes and integrons, and routine water quality parameters,
covering absolute concentrations and mass loadings. Novel approaches were
developed and applied to advance environmental microbiome and resistome
research. To investigate relationships, standardised 'effect sizes' (Cohen's D) were
introduced for AR monitoring to improve comparability of field studies. Quantitative
microbiome profiling (QMP) was applied to overcome biases caused by relative taxa
abundance data. In addition, Hill numbers were introduced as a unified diversity
framework for environmental microbiome research. Overall, water quality generally
declined, and environmental AR levels increased as one moved downstream the
catchment without major seasonal variations, except total antibiotic concentrations
that were higher in the dry season (Cohen's D > 0.8, P < 0.05). Among simple
surrogates, dissolved oxygen (DO) most strongly correlated (inversely) with total AR
gene concentrations (Spearman’s ρ 0.81, P < 0.05). This is suspected to result from
minimally treated sewage inputs, which also contain AR bacteria and genes,
depleting DO in the most impacted reaches. Thus, although DO is not a measure of
AR, relatively lower DO levels reflect wastewater inputs, flagging possible AR hot
spots. Furthermore, DO is easy-to-measure and inexpensive, already monitored in
many catchments, and exists in many numerical water quality models (e.g., oxygen
sag curves). Therefore, combining DO data and prospective modelling (e.g., with the
watershed model HSPF) could guide local interventions, especially in LMIC rivers
with limited data
Optogenetic investigation of cortical network dynamics in epilepsy
Get PDFPh. D. ThesisUnderstanding the cortical network properties which determine the susceptibility of cortex to the onset of seizures remains a major goal of epilepsy research. The determinants of seizure risk in cortical networks are dynamic, showing dependency on intrinsic cortical activity and environmental influences. The failure to identify reliable electrographic indicators of imminent seizure onset suggests that the contributory factors may not be electrographically obvious. A strong candidate for such a property is the activity dependent disinhibition of the excitatory network which results from increases in intracellular chloride concentration. Chloride loading has been shown previously to occur during periods of intense neuronal activity, resulting from concomitant excitatory and inhibitory synaptic transmission. To explore how network dynamics evolve from a stable healthy state to one permissive for the onset and propagation of seizures, I used an optogenetic approach to selectively interrogate dynamic changes to excitatory transmission between the principal cells of the cortical circuit following an acute ictogenic challenge, both in vitro and in vivo.
Using ultra-low frequency optogenetic stimulation genetically targeted to the pyramidal cells of neocortex, I demonstrate that epileptiform activity, which develops spontaneously following an acute chemoconvulsant challenge, can both be reduced and monitored, using an active probing strategy. Delivering continuous and focal optogenetic stimulations to superficial neocortex and regions of the hippocampal formation evokes glutamatergic responses in the LFP which can be used to assay dendritic excitability in the network. At ultralow frequencies, between 0.1-0.033 Hz, optogenetic stimulation markedly reduced the rate of evolution of epileptiform activity, when delivered to neocortex or hippocampal structures, in acutely prepared adult mouse brain slices bathed in 0Mg2+ perfusate.
The response evoked by these test pulses undergoes an all-or-nothing transformation observable in the LFP which reliably telegraphed the onset of ictal activity in two models of epilepsy. Using electrophysiological tools and 2-photon calcium imaging of individual dendrites, I demonstrate that this phenomenon likely reflects a reduction in the threshold for dendritic spikes. Using an anatomically realistic computational model pyramidal cell I show that this effect is reproduced by modest positive shifts in the GABAergic reversal potential in distal pyramidal cell dendrites.
Finally, I report preliminary data demonstrating a potential mechanism for the diurnal modulation of seizure risk. Diurnal periodicity in seizure susceptibility have been observed longitudinal recordings from both patients and chronically epileptic experimental animals. Using the optical chloride sensor ClopHensor I examine steady-state pyramidal cell chloride concentration over the diurnal period and show that periodicity in chloride homeostasis is consistent with the phase of diurnally modulated seizure risk.
In this thesis I use a range of optical and electrophysiological tools to explore the contribution of dynamic chloride concentration in pyramidal cells in determining cortical susceptibility to seizures onset. Using two acute epilepsy models I demonstrate that an assayable increase in dendritic excitability precedes ictogenesis, and demonstrate a potential mechanism by which variation in [Cl-]i can give rise to this effect. I go on to show diurnal variation in [Cl-]i in cortical pyramidal cells, and link this to circadian modulation of susceptibility to chemoconvulsants, suggesting a functional mechanism for the dynamic seizure risk observed in epileptic patients
Advanced deep neural networks for speech separation and enhancement
Get PDFPh. D. Thesis.Monaural speech separation and enhancement aim to remove noise interference from the noisy speech mixture recorded by a single microphone, which
causes a lack of spatial information. Deep neural network (DNN) dominates speech separation and enhancement. However, there are still challenges in DNN-based methods, including choosing proper training targets
and network structures, refining generalization ability and model capacity
for unseen speakers and noises, and mitigating the reverberations in room
environments. This thesis focuses on improving separation and enhancement
performance in the real-world environment.
The first contribution in this thesis is to address monaural speech separation and enhancement within reverberant room environment by designing
new training targets and advanced network structures. The second contribution to this thesis is on improving the enhancement performance by proposing a multi-scale feature recalibration convolutional bidirectional gate recurrent unit (GRU) network (MCGN). The third contribution is to improve the
model capacity of the network and retain the robustness in the enhancement
performance. A convolutional fusion network (CFN) is proposed, which exploits the group convolutional fusion unit (GCFU).
The proposed speech enhancement methods are evaluated with various
challenging datasets. The proposed methods are assessed with the stateof-the-art techniques and performance measures to confirm that this thesis
contributes novel solution
Mitochondrial dysfunction as a driver of cellular senescence
Get PDFPh. D. ThesisCellular senescence is a stress response implicated in ageing and age-related diseases (Baker et
al., 2016; von Zglinicki, 2002). Senescent cells are characterised by mitochondrial dysfunction
(Dalle Pezze et al., 2014; Korolchuk et al., 2017; Passos et al., 2007). Importantly,
mitochondria were shown to regulate the senescence-associated secretory phenotype (SASP)
(Correia-Melo et al., 2016). However, the exact mechanisms via which mitochondria contribute
to the SASP as well as its conservation between the main studied models of senescence, remains
to be elucidated.
In this thesis, I discovered that senescent cells are characterized by a sub-lethal
mitochondrial apoptotic stress, consisting of the activation of pro-apoptotic factor, BAX and
the release of cytochrome c and mtDNA into the cytosol. BAK and BAX are required for the
SASP in damage-induced senescence (DIS), however, their genetic depletion in oncogeneinduced senescence (OIS), increases it. A pharmacological inhibition of BAX after the
establishment of cell cycle arrest, ameliorates SASP in OIS. Cells in DIS secrete higher levels
of mtDNA than proliferating cells. However, the level of circulating mtDNA is not a strong
biomarker of senescence burden in mice and humans.
Next, I demonstrate OIS and DIS are characterised by a different degree of
mitochondrial apoptotic stress as well as oxidative phosphorylation (OXPHOS) dysfunction.
Mitochondrial network was confirmed to be hyperfused in DIS (Dalle Pezze et al., 2014),
however, it was found to be fragmented in OIS. Interfering with mitochondrial dynamics by
inducing mitochondrial fusion exacerbates the SASP in both models of senescence. In contrast,
a shift to mitochondrial fragmentation reduces the SASP in the model of DIS and exacerbates
it in OIS.
Finally, I found myxovirus resistance protein B (MxB) plays an important function in
maintaining the integrity of mitochondrial network and mitochondrial bioenergetics, as MxB
depletion induces mitochondrial apoptotic stress and activates mitochondrial biogenesis. In
DIS, MxB is highly up-regulated and translocates from mitochondria to the nucleus. MxB was
found to be a key factor required for the SASP development.Medical Research Council and Mayo Clini
The automatic classification of canine state
Get PDFPhD ThesisOsteoarthritis is a prevalent disease among domestic dogs which, even when well managed, often causes bouts of chronic pain and a lesser quality of life. Despite a
lack of training dog owners are relied upon to recognise the signs of pain or illness in
their animals. This often leads to treatment being sought later than would be ideal,
resulting in the unnecessary and avoidable suffering of their dogs. This can be further
compounded by the qualitative nature of lameness assessment performed by veterin arians. The difficulty of which is further exacerbated when symptoms are subtle, and
the disease is in its early stages. This thesis investigates the use of remote, animal borne, tri-axial accelerometers to supplement the welfare information available to both
caregivers and veterinarians. Published acceleration-derived measures, of both the
time and frequency domains, common within human and non-human animal acceler ometer research, are assessed for their potential as daily and weekly identifiers of os teoarthritic lameness. The suitability of identified measures was evaluated using both
Principal Component Analysis based feature selection and logistic linear models. The
results of this process highlighted a potential link between both the level and entropy of
an animals overall weekly activity with the occurrence of osteoarthritis. It also provided
insight into areas of further development and established the complexity of the task of
recognising lameness from acceleration data. A behaviour-based methodology was
established hybridising techniques used across wildlife ecology deployments, existing
veterinary assessment of lameness and, the assessment of human gait impacted by
both physical illness and neurodegeneration. This led to the development of a method ology focussing on the identification of behaviours, starting with canine postural state,
to provide context as to the daily activities of the subject. Two distinct approaches to
postural recognition were assessed both employing machine learning techniques with
a focus on the interpretability of results. The first, examined the identification of 6 pos tural transitions, similar to methods established in human accelerometer assessments,
using linear discriminant analyses at 3 different sliding window lengths. The inclusion
of an empirical cumulative distribution function representation was also assessed. The
results suggested that the isolation of transitional periods from among non-transitional
periods was difficult and there was high confusion between the transitions themselves.
The second examined the identification of the postures themselves alongside the oc currence of locomotion during the standing posture. Linear discrimination analyses
were once again used due to the interpretability of the method and the simplicity of its
implementation. The effects of pre-processing techniques and differing posture group ings were also explored. The findings suggested a binary decision tree approach was
the most effective mechanism and that the application of pre-processing techniques to
clean data caused a distinct negative impact that requires forethought as to the poten tial costs and benefits of their use. Standing was the most easily identified, perhaps
due to its prominence, and the further classification of locomotion from among stand ing periods was ineffective. To further supplement the postural methods of identifying
osteoarthritis an investigation of the remote monitoring of circadian rhythm was estab lished. This is of interest due to prior results highlighting the potential relationship of
activity entropy and level with lameness and the reports of sleep disruption by human
chronic pain sufferers. Features relating to the length and frequency of both resting
and active bouts were used in logistic regression models to establish their relationship
to the presence or absence of osteoarthritis. Minor disruption was observed to the
amplitude of activity frequencies within osteoarthritic dogs consistent with prior find ings. However, further work is needed to disentangle this effect from that of advanced
age, a possible confound. The potential of remote sensing technologies is shown but
further development of methodologies is required. A combination of the described
approaches, with the refinements highlighted within this thesis, could further improve
their efficacy and should be investigated. A behaviour based, transparent and fully in terpretable monitor of lameness, pain, and/or welfare could prove valuable to the early
and effective treatment of canine osteoarthritis and should be pursued furthe
Internal gravity waves in massive stars
Get PDFPh. D. ThesisIntermediate-mass stars in the main-sequence have radiative envelopes and convective
cores. This configuration allows internal gravity waves (IGWs), generated stochastically
at the convective-radiative boundary, to propagate through the radiation zone and produce signatures, which can be observed through space-based photometry and groundbased spectroscopy. In this thesis, we present results from the investigation of IGWs in
intermediate-mass stars through theoretical and numerical studies.
The study of IGWs in intermediate-mass stars can be broken down into IGW propagation and IGW generation. In our work, we start with the study of IGW propagation
in the linear regime. In this regime, IGW amplitudes are affected by three main features:
radiative diffusion, density stratification and geometric effects. We study the implications
of these three features on waves travelling within the radiative zones of non-rotating stars.
As a simple measure of induced wave dynamics, we define a criterion to see if waves can
become nonlinear and if so, under what conditions. We find that the IGW generation
spectrum, convective velocities and the strength of density stratification all play major
roles in whether waves become nonlinear. With increasing stellar mass, there is an increasing trend in nonlinear wave energies. The trends with different metallicities and ages
depend on the generation spectrum.
Next, we move onto the study of non-linear IGW propagation using two-dimensional
fully non-linear hydrodynamical simulations with realistic stellar reference states up to
the stellar surface. When a single wave is forced, we observe wave self-interaction. When
a spectrum of waves is forced, we find that the surface IGW frequency spectrum follows
a power law with a slope consistent with recent observations. This power law is similar
to that predicted by linear theory for the wave propagation, with small deviations which
can be an effect of nonlinearities. When the same generation spectrum is applied to 3
M models at different stellar rotation and ages, the surface IGW spectrum slope is very
similar to the generation spectrum slope.
Finally, we study the IGW generation frequency spectrum from non-linear simulations
of core convection as functions of stellar mass and age for intermediate-mass stars. This
is an ongoing project and the current results show that the generation frequency slopes
lie between -0 and -1 at lower frequencies, and between -1.5 and -3 at higher frequencies
for all the stellar models, with the high-frequency slope of the 3M ZAMS model being
consistent with previous numerical work (Rogers et al., 2013).BEIS capital funding via STFC capital grants ST/P002293/1 and ST/R002371/1, Durham University and STFC operations
grant ST/R000832/1
Impact of computer-assisted pronunciation training on child English language learners
No full textPh. D. Thesis. (Integrated)Understanding second language speech has been a pressing issue for
researchers. Accounts for sources of error shown by L2 learners include age of
initial exposure, relative markedness, L1 functional constraints, speci cally
perceptual salience and frequency (Colantoni and Steele, 2008), and perception,
which is the basis for explaining cross-linguistic in
uence by most L2 speech
learning theories (Colantoni, Steele, and Escudero, 2015), but they do not
include the delay of oral production. When we look at younger beginner L2
learners, L1 in
uence can also be observed. The aim of the present study was to
address the impact of delaying oral production and for this computer-assisted
pronunciation training (CAPT) was used on Arabic-speaking children in Libya
learning English as a second language with no prior instruction in English.
English instruction in Libya is typically delivered by non-native teachers whose
non-native input is also a possible source of L1 in
uence. The software provided
native speaker input to address this additional aim. Within the software, test
words were presented in orthographic and audio formats with pictures depicting
meaning. Predictions on the role of output have varying underlying assumptions.
Proponents of the importance of production practice such as Swain (1985; 1995;
2005) and Mackey (2007) argue that it is a tool for creating novel linguistic
knowledge and promoting cognitive processes (see Colantoni and Steele, 2008 in
their Hybrid model).
Following a three-week training with use of the software, 38 seven-year-old
participants took part in picture-naming, read aloud and delayed repetition tasks
in an immediate post-test and, of these, 30 took part in similar tasks for a
delayed post-test 10 weeks later. The 38 participants were divided into two
training conditions, Listen and Speak (n.=20) and Listen Only (n.=18) to test
the role of delayed production on L2 learning. Another group of 20 aged-matched
participants took part in a three-week training with use of Traditional Teaching
and participated in the same tasks in an immediate post-test and of these 18
took part in similar tasks for a delayed post-test 10 weeks later. The Traditional
Teaching condition was added to compare input type on participants within the
same age group.
The aspects of pronunciation measured were target-likeness rating, match
rating, various acoustic cues including Voice Onset Time (VOT), vowel-onset
fundamental frequency, and spectral tilt (Ahi-A23). The participants' L2 values
were compared to the target language and their L1 values to test predictions
made by models of speech learning. The phonetic data revealed signs of merger
categories between L1 and L2 corroborating the ndings of Flege (1995) and
MacKay, Flege, Piske, and Schirru (2001). Additionally, phonological processes
were examined and compared to processes found in L1 English child phonology.
The amount of lexical learning was also explored. Results for TL-likeness and
match rating revealed that the experimental conditions statistically outperformed
the Traditional condition in both tests. In the delayed test however, the Listen
and Speak condition statistically outperformed Listen Only participants, who
continued to outperform the Traditional learners. VOT and vowel-onset f0
analyses revealed that participants from all training conditions failed to establish
independent L2 categories. Rather, they illustrated intermediate values
resembling both native and target phonetic categories. In terms of lexical
learning, the experimental conditions outperformed the Traditional condition in
terms of the amount of fully learned words in the delayed repetition and
picture-naming task but they all performed the same in the read aloud task.
Some interlanguage processes were demonstrated by the learners in addition to
the expected transfer from their Arabic variety. These varied depending on the
sound class and conformed to universal language development and input from
native speakers of the target language. It is concluded that the ndings support
the importance of output in language learning for L1 beginning-level children in
the classroom as suggested by the Hybrid model (Colantoni and Steele, 2008).Libyan Ministry of Educatio
Fluorescent Nanomaterials from Biomass: Synthesis and Applications
Get PDFPh. D. Thesis.Energy crisis, environmental deterioration and dwindling fossil resources are the rising global
concerns. As a result, utilising biomass waste as a green and renewable resource into valueadded materials is highly appealing for the sustainable world. Among various materials
explored, carbon and its derivatives attract much more attention due to their intriguing
properties and broad range of applications.
This work focused on the conversion of biomass into activated carbon (AC) and its further
development into fluorescent carbon nanomaterials for the energy and sensing applications.
‘Spent tea’ was selected as a food waste feedstock. A systematic study was carried out to
produce char by pyrolysis and activate it using chemical activation. Consequently, a series of
ACs with varying levels of porosity and surface areas (10 to >2000 m2
g
-1
) were produced. These
ACs were employed as an alternate electrode material to study the effect of porosity on the
charge transfer in vanadium redox flow battery.
A thorough investigation on the further transformation of char into fluorescent nanomaterials
lead to the production of graphene quantum dots (GQDs). An upgraded approach was adopted
for the purification of these GQDs. The results showed that GQDs possessed 3-5 layered
graphene structure with a size range of 2-20 nm and band gap varying from 2.67 to 2.95 eV.
Under the premise of acquiring high yield, the activation and synthesis steps were combined
into a single-step microwave treatment and GQDs were synthesised with a high yield of ~84%.
Finally, the intensified and green synthesis of GQDs was accomplished under the direct
hydrothermal carbonisation of biomass waste. The as-prepared GQDs were applied to design a
selective and sensitive sensor for Fe3+ ions with a detection limit of as low as 2.5 x 10–6 M. The
present work highlights the significance of preparing high-value nanomaterials from little value
biomass waste.EPSR