Prosopis farcta (Banks & Sol.) J. F. Macbr. has been reported for the first time from Libya. This species is native in Asia. Flowering specimens of Prosopis farcta collected from Sokna Region about 650 Km south-east Tripoli. It is presented with updated nomenclature, taxonomic description, geographical distribution, place of occurrence in Libya, and field colored photographs are also provided. The voucher specimens were deposited in the Herbarium of Botany Department (ULT), University of , Tripoli, Libya.

A novel non-blind audio watermarking algorithm, using chirp z-transform in combination with discrete wavelet transform and singular value decomposition, is presented in this paper. In the proposed method, a watermark audio signal (about 13 seconds in length) is hidden into an original audio signal (about 51 seconds in length) by applying discrete wavelet transform, chirp z-transform, and singular value decomposition. The effectiveness of the proposed algorithm has been tested using signal-to-noise ratio, objective difference grade (ODG), and normalised cross- correlation of watermarked audio signal under various common audio attacks. Experimental results demonstrate that the algorithm has a high capacity (352.8 kbps), without significant perceptual distortion (ODG > -0.29) and provides good robustness against common audio attacks, including: re-sampling, echo addition, MP3 compression, additive white Gaussian noise, re- quantisation, cutting, and low-pass filtering. This algorithm has a high capacity and excellent audio quality compared with other audio watermarking algorithms.

ABSTRACT

Natural polymers with improved structure have been securing increasing value in the industry as they

are abundant, cheap, and biodegradable. Graft copolymerization is one of the effective ways to

enhance the properties of natural polymers. Starch based graft copolymers are becoming increasingly

important due to their remarkable adhesion, high water absorbency, and biodegradability. Methyl

methacrylate (MMA) grafted onto starch by using the ceric ammonium nitrate (CAN) as a redox

initiator in the presence of nitric acid in aqueous medium to form grafted copolymer (Starch-g-

PMMA) was investigated. The grafting reaction was carried out under stream of nitrogen gas. The

impact of different reaction parameters to achieve the highest percent grafting (%G) has been studied

by determining the initiator concentration, monomer concentration, time (hours), nitric acid

concentration, and polymerization temperature. The % G was found to be 97%. Evidence of grafting

was characterized and confirmed by Fourier transform infrared spectroscopy (FTIR). The peaks at

1736.70 cm-1 and 3449.78 cm-1 indicates that MMA has been successfully grafted to starch. %G was

found to be decreased at higher than 70°C, after 2 hours of reaction time, with an increase of MMA

monomer concentration, initiator concentration, and with HNO3 concentration. The highest percent

grafting was obtained at the parameters of 1 g starch, 70°C, 2 hours, 2 mmol CAN, 140 mmol MMA

and 0.4 mmol HNO3

A floristic survey of Sedrores Al-Qawasim mountains in Gharyan district - Libya was conducted in two consecutive growing seasons from 01/04/2018 to 01/6/2019. In this study area, a total number of 320 plant species belonging to 214 genera were collected representing 44 families, of which 39 families and 276 species belonging to dicotyledons, and 5 families and 44 species are belonging to monocotyledons. The results showed the dominance of the family Asteraceae with 60 species, followed by the family Fabaceae with 32 species, then the family Poaceae with 29 species. The results showed the dominance of the (Euphorbia genus) with 7 species, followed by Helianthenum, Plantago and Erodium with 6 species each. Moreover, life-form spectrum analysis showed the predominance of therophytes with 210, followed by Hemicryptophytes with 59 species, while chorotype spectrum analysis showed the dominance of Mediterranian species with 151 species, followed by Mediterrean/Iranu-Turanean with 72 species. 

Abstract:

This study investigated the potential use of olive pomace (OP) as an adsorbent to

reduce the concentration of methyl orange (MO) in aqueous solutions. The effect of

some important parameters on the process of adsorption was examined, including

pH, adsorbent weight, temperature, contact time, agitation speed, and the initial

concentration of MO. The results showed that the optimum concentration of MO was

10 ppm and the optimum pH = 2, indicating that the process of MO adsorption on the

surface of the OP was better in acidic medium. The equilibrium time was 80 min at a

speed of 100 rpm. The results of the study showed the significant role of OP weight,

agitation speed, temperature and the contact time in increasing the adsorption

efficiency. On comparing the pseudo first order and pseudo second order models, the

results showed that the pseudo second order model fitted the experimental data well.

The study also included testing of Langmuir and Freundlich models on the

adsorption isotherm data, and it was found that experimental data obey the

Freundlich isotherm. To sum up, the study showed that OP has high adsorption

efficiency to remove MO by applying a simple, inexpensive method.

Watermarking techniques have been considered as one of the best efficacious methods 

to solve the issues of protecting copyright due to the proliferation of digital multimedia 

information on the internet. The digital multimedia information is such as image, 

audio, and video which can today be easily copied, distributed, and modified without 

loss in fidelity. As a result, it is necessary to utilize some kind of copyright protection 

techniques to avoid illegal copying, distribution, and digital copyright modification. 

The digital watermarking techniques have engaged the researchers’ attention as a 

technique for protecting copyright in the digital multimedia information. This 

technique includes a subcategory of information-hiding technologies in which the 

ownership information is hidden into the original multimedia information without 

impacting the original multimedia information quality. Despite the advances in digital 

watermarking techniques, the main objective of many types of research in digital 

watermarking topic is to improve transparency and resistance to attacks and the present 

digital watermarking schemes are not sufficiently stable or strong against various 

attacks. This study aims to develop state-of-the-art digital watermarking techniques 

for different multimedia information through improving the imperceptibility and 

robustness to geometrical attacks and signal processing operations. Four novel robust 

blind digital watermarking schemes are introduced in this thesis for copyright 

protection of multimedia information that have not been previously introduced. The 

first robust blind digital watermarking scheme is applied for colour images utilizing 

discrete wavelet transform in combination with Walsh Hadamard transform and 

Hessenberg decomposition. The second robust blind digital watermarking scheme is 

applied for grayscale images utilizing discrete wavelet transform in combination with 

Walsh Hadamard transform and Hessenberg decomposition. The third robust blind 

digital watermarking scheme is applied for colour videos utilizing discrete wavelet 

transform in combination with Walsh Hadamard transform and Hessenberg 

decomposition. Forth robust blind digital watermarking scheme is applied for audio 

signals utilizing discrete wavelet transform in combination with Walsh Hadamard 

transform and Hessenberg decomposition. Several experiments are performed in order 

to present the effectiveness of the proposed digital watermarking schemes in terms of 

imperceptibility and robustness against attacks related to each scheme. The proposed 

digital watermarking schemes achieve good imperceptibility and robustness against 

geometrical attacks and signal processing operations. The proposed digital 

watermarking schemes have a superior performance in terms of imperceptibility and 

robustness than other reported schemes in the literature.

Keywords: Watermarking, Copyright Protection, Discrete Wavelet Transform, Walsh 

Hadamard Transform, Hessenberg Decomposition.

A new record for Abutilon theophrasti is recorded for the first time in the flora of Libya. This widespread agricultural weed was collected from El-Hamra region (El-Qabel) in the Nafusa Mountain south of Tripoli. To facilitate further identification and future detection, a full description, habitat information, distribution map and distribution data are provided. A brief discussion about the most important threats posed by this species is presented.